Spondylocostal dysostosis associated with anal and urogenital anomalies in a Mennonite sibship

Spondylocostal Dysostosis with Anal Atresia and Urogenital Anomalies in a Young Infant: First Case Entity of Casamassima–Morton–Nance Syndrome from Asia

Casamassima–Morton–Nance syndrome (CMNS) includes a heterogeneous group of spondylocostal dysostosis along with anal atresia and genitourinary abnormalities. In 1981, Casamassima et al first described the syndrome in a fetus, and since then, only seven such cases have been reported so far. CMNS phenotype shows a significant clinical variability as documented in the reported cases. Etiology remains unknown yet, and it carries a poor prognosis. Here, we reported on a young female infant born out of nonconsanguineous marriage with normal karyotype and spondylocostal dysostosis, anal and genitourinary malformations suggesting CMNS. Ours is the eighth, and first case entity of CMNS reported from Asia as per the literature search. In our case, the additional feature of bilateral clubfoot has not been documented earlier in the literature. It extends the clinical spectrum of the syndrome and prompts us to consider it a close differential diagnosis to VACTERL (vertebral defects, anal atresia, cardiac malformations, tracheoesophageal fistula/esophageal atresia, renal anomalies, limb abnormalities) syndrome, which is commonly known and diagnosed. It also raises the question of whether cases of CMNS are being misdiagnosed as VACTERL syndrome due to its rarity.

Diagnostic strategy in segmentation defect of the vertebrae: a retrospective study of 73 patients

Background

Segmentation defects of the vertebrae (SDV) are non-specific features found in various syndromes. The molecular bases of SDV are not fully elucidated due to the wide range of phenotypes and classification issues. The genes involved are in the Notch signalling pathway, which is a key system in somitogenesis. Here we report on mutations identified in a diagnosis cohort of SDV. We focused on spondylocostal dysostosis (SCD) and the phenotype of these patients in order to establish a diagnostic strategy when confronted with SDV.

Patients and methods

We used DNA samples from a cohort of 73 patients and performed targeted sequencing of the five known SCD-causing genes (DLL3, MESP2, LFNG, HES7 and TBX6) in the first 48 patients and whole-exome sequencing (WES) in 28 relevant patients.

Results

Ten diagnoses, including four biallelic variants in TBX6, two biallelic variants in LFNG and DLL3, and one in MESP2 and HES7, were made with the gene panel, and two diagnoses, including biallelic variants in FLNB and one variant in MEOX1, were made by WES. The diagnostic yield of the gene panel was 10/73 (13.7%) in the global cohort but 8/10 (80%) in the subgroup meeting the SCD criteria; the diagnostic yield of WES was 2/28 (8%).

Conclusion

After negative array CGH, targeted sequencing of the five known SCD genes should only be performed in patients who meet the diagnostic criteria of SCD. The low proportion of candidate genes identified by WES in our cohort suggests the need to consider more complex genetic architectures in cases of SDV.

Congenital hemangioma in spondylocostal dysostosis: a novel association

Congenital hemangioma is a benign tumor caused by dysfunction in embryogenesis and vasculogenesis, which progresses during fetal life to manifest as fully developed at birth. Although hemangiomas are the most common tumor of infancy, rapidly involuting congenital hemangioma has not been described in spondylocostal dysostosis. I report the novel association of congenital hemangioma and spondylocostal dysostosis in a Mexican newborn female patient with neural tube defects. Given the embryological relationship between skin and nervous system, I surmise that this association is not coincidental. I also propose that these morphologic alterations be incorporated to the spondylocostal dysostosis phenotype and specifically looked for in other affected children, in order to provide appropriate medical management and genetic counseling.

Fetus with Casamassima-Morton-Nance Syndrome and Limb-Body Wall Defect: Presentation of a Novel Association and Review of the Phenotype

In 1981, Casamassima and colleagues described an autosomal recessive syndrome of spondylocostal dysostosis associated with anal and urogenital anomalies. Here, I describe 1 new fetus who presented with limb-body wall defect as a novel association, compile 7 patients, and review the clinical phenotype of Casamassima-Morton-Nance syndrome. This appears to be the 1st Casamassima-Morton-Nance syndrome fetus with this complex malformation. In light of this manifestation, a detailed comparative phenotypic analysis of published patients revealed a heterogeneous syndrome with significant clinical variability. Accordingly, it is proposed that Casamassima-Morton-Nance syndrome should be considered in those patients with the combination of a short and asymmetric thorax with rib and vertebral anomalies and scoliosis (spondylocostal-like pattern), anal atresia, absent external genitalia, renal and urethral abnormalities (caudal dysgenesis complex), craniofacial dysmorphic features (mainly flat nose with anteverted nares, low-set/abnormal ears, and short neck), hydrops, oligohydramnios, and a poor clinical outcome.

A new case of Casamassima-Morton-Nance (CMN) syndrome presenting prenatally as VACTERL association

Casamassima-Morton-Nance (CMN) syndrome (OMIM 271520) has clinical overlap with spondylocostal dysostosis and Vertebral, Anorectal, Cardiac, Tracheo-Esophageal, Radial/Renal, Limb (VACTERL) association but with consistent features of anal and urogenital abnormalities, particularly ambiguous genitalia. Since the original report, it has become clear that the combination of vertebral segmentation abnormalities, rib abnormalities, and urogenital anomalies may enable prenatal diagnosis of CMN by ultrasound. CMN syndrome is an important diagnosis to consider prenatally because of the generally poor prognosis compared to the more common VACTERL association. Here we present the seventh reported case of CMN syndrome. Prenatally presenting features of multiple segmentation anomalies within the spine, a left multi-cystic dysplastic kidney, marked pelvicaliectasis with abnormal renal parenchyma and a small stomach were suggestive of VACTERL association. There was severe oligohydramnios. Termination of pregnancy was performed at 22 weeks gestation and autopsy revealed dysmorphic coarse facial features, marked scoliosis, bilateral talipes, ambiguous external genitalia, and anal atresia. These features were highly suggestive of CMN syndrome. The important discriminating feature of ambiguous genitalia was not apparent on the prenatal ultrasound in this case because of severe oligohydramnios but we suggest that careful prenatal ultrasound assessment of the genitalia in cases of suspected VACTERL is important in differentiating these two conditions.

Pilot assessment of a radiologic classification system for segmentation defects of the vertebrae

Existing nomenclature systems for describing and reporting congenital segmentation defects of the vertebrae (SDV) are confusing, inconsistently applied, and lack molecular genetic advances. Our aim was to develop and assess a new classification system for SDV. A multidisciplinary group of the International Consortium for Vertebral Anomalies and Scoliosis (ICVAS) developed a new classification system for SDV, and 5 members group (Group 1) independently classified 10 previously unseen cases using this system. Inter-observer reliability was assessed using kappa, which compares observed agreement with that expected by chance. Seven independent general radiologists unaffiliated with the ICVAS (Group 2) classified the same 10 cases (total, 70 scores) before and after the ICVAS system was explained. We demonstrated the following: Inter-observer reliability for Group 1 yielded a kappa value of 0.21 (95% confidence intervals (CI) 0.052, 0.366, P = 0.0046); A consensus diagnosis was established for the 10 cases. For Group 2, before the ICVAS system was explained, 1 of 70 scores (1.4%) agreed with the Group 1 consensus diagnoses; Group 2 offered 12 different diagnoses, but 38 of 70 (54.3%) responses were "Don't Know." After the ICVAS system was explained, 47 of 70 responses (67.1%; 95% CI 55.5, 77.0) agreed with the Group 1 consensus, an improvement of 65.7% (95% CI 52.5, 75.6, P < 0.00005), with no "Don't Know" responses. Group 2 average reporting times, before and after explanation of the ICVAS system, were 148 and 48 min, respectively. We conclude that the ICVAS radiological classification system was found to be reliable and applicable for 10 SDV phenotypes.

Genetics of Hirschsprung disease and anorectal malformations

Hirschsprung disease (HD) and anorectal malformations (ARMs) result from alterations in hindgut development. It has long been recognized that both recur in families and thus result, at least in part, from genetic factors. Progress in the understanding of the genetic basis of HD has been made by the application of findings from genetic animal models of altered enteric nervous system development to human beings. Several genes have been shown to be important for human enteric nervous system development, and current work is progressing to identify genetic interactions that may explain the variable phenotype of HD. By contrast, understanding of the genetic factors underlying ARMs is much less developed. We and others have shown that genetic factors play an important role in the pathogenesis of ARMs, and many mouse genetic models suggest molecular pathways that may be altered in ARMs.

Defective somitogenesis and abnormal vertebral segmentation in man

In recent years molecular genetics has revolutionized the study of somitogenesis in developmental biology and advances that have taken place in animal models have been applied successfully to human disease. Abnormal segmentation in man is a relatively common birth defect and advances in understanding have come through the study of cases clustered in families using DNA linkage analysis and candidate gene approaches, the latter stemming directly from knowledge gained through the study of animal models. Only a minority of abnormal segmentation phenotypes appear to follow Mendelian inheritance but three genes--DLL3, MESP2 and LNFG--have now been identified for spondylocostal dysostosis (SCD), a spinal malformation characterized by extensive hemivertebrae, trunkal shortening and abnormally aligned ribs with points of fusion. In affected families autosomal recessive inheritance is followed. These genes are all important components of the Notch signaling pathway. Other genes within the pathway cause diverse phenotypes such as Alagille syndrome (AGS) and CADASIL, conditions that may have their origin in defective vasculogenesis. This review deals mainly with SCD, with some consideration of AGS. Significant future challenges lie in identifying causes of the many abnormal segmentation phenotypes in man but it is hoped that combined approaches in collaboration with developmental biologists will reap rewards.

Abnormal vertebral segmentation and the notch signaling pathway in man

Abnormal vertebral segmentation (AVS) in man is a relatively common congenital malformation but cannot be subjected to the scientific analysis that is applied in animal models. Nevertheless, some spectacular advances in the cell biology and molecular genetics of somitogenesis in animal models have proved to be directly relevant to human disease. Some advances in our understanding have come through DNA linkage analysis in families demonstrating a clustering of AVS cases, as well as adopting a candidate gene approach. Only rarely do AVS phenotypes follow clear Mendelian inheritance, but three genes-DLL3, MESP2, and LNFG-have now been identified for spondylocostal dysostosis (SCD). SCD is characterized by extensive hemivertebrae, trunkal shortening, and abnormally aligned ribs with points of fusion. In familial cases clearly following a Mendelian pattern, autosomal recessive inheritance is more common than autosomal dominant and the genes identified are functional within the Notch signaling pathway. Other genes within the pathway cause diverse phenotypes such as Alagille syndrome (AGS) and CADASIL, conditions that may have their origin in defective vasculogenesis. Here, we deal mainly with SCD and AGS, and present a new classification system for AVS phenotypes, for which, hitherto, the terminology has been inconsistent and confusing.

The vertebrate segmentation clock and its role in skeletal birth defects

The segmental structure of the vertebrate body plan is most evident in the axial skeleton. The regulated generation of somites, a process called somitogenesis, underlies the vertebrate body plan and is crucial for proper skeletal development. A genetic clock regulates this process, controlling the timing of somite development. Molecular evidence for the existence of the segmentation clock was first described in the expression of Notch signaling pathway members, several of which are expressed in a cyclic fashion in the presomitic mesoderm (PSM). The Wnt and fibroblast growth factor (FGF) pathways have also recently been linked to the segmentation clock, suggesting that a complex, interconnected network of three signaling pathways regulates the timing of somitogenesis. Mutations in genes that have been linked to the clock frequently cause abnormal segmentation in model organisms. Additionally, at least two human disorders, spondylocostal dysostosis (SCDO) and Alagille syndrome (AGS), are caused by mutations in Notch pathway genes and exhibit vertebral column defects, suggesting that mutations that disrupt segmentation clock function in humans can cause congenital skeletal defects. Thus, it is clear that the correct, cyclic function of the Notch pathway within the vertebrate segmentation clock is essential for proper somitogenesis. In the future, with a large number of additional cyclic genes recently identified, the complex interactions between the various signaling pathways making up the segmentation clock will be elucidated and refined.

Spondylocostal dysostosis, anal and genitourinary malformations in a fetal case: A new case of Casamassima–Morton–Nance syndrome?

Casamassima-Morton-Nance syndrome belongs to the heterogeneous group of spondylocostal dysostoses (SCD) represented by a large heterogeneous group in which diverse diagnoses, associations and modes of inheritance are found. Common features include segmentation abnormalities of the vertebrae and ribs. Here, we report on a fetal case with spondylocostal dysostosis, anal and genitourinary malformations and discuss Casamassima-Morton-Nance syndrome.

Costovertebral dysplasia in a patient with partial trisomy 22

A newborn female presented with costovertebral dysplasia (CVD), subtle facial anomalies, and neonatal respiratory distress. Her karyotype demonstrated a small supernumerary NOR-positive marker that was subsequently identified as del(22)(q11.2). This extra structurally abnormal chromosome was found by DNA microsatellite marker analyses to be derived from a paternal chromosome 22. The child has had severe growth and developmental delay along with pulmonary insufficiency and hypoxia but is presently stable at age 20 months. Findings in our patient correlate with similar observations in children with small markers derived from D/G and D/D translocations reported before banding technology was available. These reports and recent mapping results suggest that a pericentric gene family, distributed on one or more acrocentric chromosomes, may have played a role in the development of the human axial skeleton. Data from additional studies will be needed to confirm or refute this hypothesis.

Segmentation anomalies of vertebrae and ribs with other abnormalities of blastogenesis: syndromes or associations?

On the basis of two recently studied human fetuses and the historical records and remnant 19th century skeletons in the Museum Vrolik in Amsterdam, we have begun an analysis of an unusual form of somite dysgenesis. This disorder includes vertebral and costal segmentation defects with or without (distal) limb malformation and deformities, anogenital anomalies, unusual colonic atresia, abdominal wall and diaphragmatic defect, Central nervous system abnormality with large head, and severe neurohypotrophic lower limb deformities. This study suggests the existence of an axial vertebral/costal dysgenesis complex with apparently or nearly normal number of cervical vertebrae. There also is some overlap with lumbosacral agenesis but different from the autosomal recessive entities Jarcho-Levin syndrome or spondylocostal dysostosis. To date, no associated heart defects have been noted.

Thoracoplasty for treatment of asphyxiating thoracic dysplasia in a newborn

In our case report and literature review, we report about a female newborn with severe asphyxiating thoracic dysplasia of the spondylocostal dysostosis classification to whom an expandable thoracoplasty with metal implants offered survival and discharge at home from newborn to infancy.

Phenotype characterization and natural history of spondylothoracic dysplasia syndrome: a series of 27 new cases

Spondylothoracic dysplasia (STD, MIM#277300) is an autosomal recessive disorder with high prevalence in the Puerto Rican population. It is generally regarded as a lethal condition. Since Jarcho and Levin described it in 1938, it has been referred to as spondylocostal dysplasia, costovertebral dysplasia, Jarcho-Levin syndrome and STD. We have prospectively characterized 27 patients with STD by detailed physical examination, pedigree analysis, thoracic CT scans, and pulmonary function tests (PFTs). Diagnoses were established using spinal radiographs and 3-D reconstructive CT scans to demonstrate fusion of the ribs at the costo-vertebral junction with a fan-like (crab-like) configuration of the thorax. Vertebral segmentation and formation defects were seen throughout the spine with a decrease in the number of vertebral bodies. Characteristic vertebral shape consisted of a decrease in antero-posterior diameter and an increase in lateral length, giving the vertebra a sickle shape. Eight out of 18 prospectively follow patients died within the first 6 months of life, a 44% mortality rate. Cause of death was respiratory insufficiency secondary to pneumonia and pulmonary restriction. This is an important finding since the vast majority of STD syndrome patients cited in the medical literature have died in the newborn and early childhood periods. Age of the remaining patients ranged from 4 months to 47 years. This represents the largest collection of patients with STD reported and it has allowed us to determine a detailed phenotype. Given 56% survival at 6 months, we show that STD is not a lethal syndrome.

Spondylocostal dysostosis: thirteen new cases treated by conservative and surgical means

STUDY DESIGN

Prospective assessment of a cohort of patients affected by spondylocostal dysostosis.

OBJECTIVE

To report on the results of conservative and operative management of spondylocostal dysostosis and, based on this, to propose an assessment and treatment protocol for the condition.

SUMMARY OF BACKGROUND DATA

Spondylocostal dysostosis and spondylothoracic dysostosis are subtypes of Jarcho-Levin syndrome, a hereditary condition manifested by vertebral body and related rib malformations. Mortality prevails in spondylothoracic dysostosis because of more severe respiratory compromise.

METHODS

Details of prenatal and postnatal diagnosis, history, and management of 13 patients with spondylocostal dysostosis are presented. All patients were treated postnatally with repeated chest physiotherapy. Two patients refractory to conservative treatment underwent surgical intervention: the first had a chest wall reconstruction via a latissimus dorsi flap, the second a posterior spinal instrumented fusion for progressive scoliosis.

RESULTS

Prenatal ultrasound in 4 of 13 cases showed full details of vertebral and rib anomalies. Thoracic and lumbar hemivertebrae were most common, leading to congenital scoliosis in 10 of 13 cases. A number of extraskeletal abnormalities were also identified. At an average follow-up of 4.5 years, the survival rate was 100% with a remarkable decrease of the rate of respiratory complications. Surgical treatment in selected cases led to satisfactory results.

CONCLUSIONS

Prenatal diagnosis of spondylocostal dysostosis allows exclusion of spondylothoracic dysostosis and aids genetic counseling in quantifying the risk to siblings. Postnatally, prompt management of these patients with physiotherapy leads to prolonged survival. Surgical intervention may then be indicated to stabilize chest wall or spine deformities, with promising results.

Pseudodominant inheritance of spondylocostal dysostosis type 1 caused by two familial delta-like 3 mutations

Spondylocostal dysostoses (SCD) are a heterogeneous group of disorders of axial skeletal malformation characterized by multiple vertebral segmentation defects and rib anomalies. Sporadic cases with diverse phenotypes, sometimes including multiple organ abnormalities, are relatively common, and monogenic forms demonstrating autosomal recessive (AR) and, more rarely, autosomal dominant (AD) inheritance have been reported. We previously showed that mutations in delta-like 3 (DLL3), a somitogenesis gene that encodes a ligand for the notch signaling pathway, cause AR SCD with a consistent pattern of abnormal segmentation. We studied an SCD family previously reported to show AD inheritance, in which the phenotype is similar to that in AR cases. Direct DLL3 sequencing of individuals in two generations identified the affected father as homozygous for a novel frameshift mutation, 1440delG. His two affected children were compound heterozygotes for this mutation and a novel missense mutation, G504D, the first putative missense mutation reported in the transmembrane domain of DLL3. Their two unaffected siblings were heterozygotes for the 1440delG mutation. Pseudodominant inheritance has been confirmed, and the findings raise potential consequences for genetic counseling in relation to the SCD disorders.

Another case of cerebro-facio-thoracic dysplasia (Pascual-Castroviejo syndrome)

We report another case of cerebro-facio-thoracic dysplasia (Pascual-Castroviejo syndrome) characterized by mental retardation and characteristic facies: narrow forehead, synophris, hypertelorism, broad nasal bridge, long philtrum, micrognathia, triangular-shaped mouth and low posterior hairline, and also brachycephaly, calcified clinoid ligaments, and upper rib deformities. Although the severity of mental retardation within the syndrome varies, the reported case shows not only a severe degree, but also cerebral malformations not reported in any of the previous cases of cerebro-facio-thoracic syndrome. These include cortical-subcortical atrophy with hypoplasia of the corpus callosum, and of the cerebellar vermis. We also discuss the inheritance pattern and differential diagnosis, comparing this phenotype to other similar dysmorphic syndromes.

Molecular genetic prenatal diagnosis for a case of autosomal recessive spondylocostal dysostosis

Autosomal recessive spondylocostal dysostosis type 1 (ARSCD1) is a member of the heterogeneous group of disorders termed the spondylocostal dysostoses that are characterized by multiple vertebral segmentation defects and rib anomalies. In these patients, the entire vertebral column is malformed and is replaced by multiple hemivertebrae giving rise to truncal shortening, abdominal protrusion and non-progressive spinal curvature. Genetic studies have shown that some cases of ARSCD are due to mutations in the somitogenesis gene, Delta-like 3 (DLL3), that encodes a ligand for the Notch signalling pathway-ARSCD type 1. To date, 17 different DLL3 gene mutations have been reported. A consanguineous family of Turkish origin with ARSCD type 1 due to a homozygous DLL3 mutation requested genetic prenatal diagnosis. Using DNA from a chorionic villus sample, both linkage analysis of the DLL3/19q region and direct sequencing for the familial mutation demonstrated that the unborn fetus was an unaffected carrier. This is the first case of molecular genetic prenatal diagnosis in any form of SCD.

Novel mutations in DLL3, a somitogenesis gene encoding a ligand for the Notch signalling pathway, cause a consistent pattern of abnormal vertebral segmentation in spondylocostal dysostosis

The spondylocostal dysostoses (SCD) are a group of disorders characterised by multiple vertebral segmentation defects and rib anomalies. SCD can either be sporadic or familial, and can be inherited in either autosomal dominant or recessive modes. We have previously shown that recessive forms of SCD can be caused by mutations in the delta-like 3 gene, DLL3. Here, we have sequenced DLL3 in a series of SCD cases and identified 12 mutations in a further 10 families. These include 10 novel mutations in exons 4-8, comprising nonsense, missense, frameshift, splicing, and in frame insertion mutations that are predicted to result in either the truncation of the mature protein in the extracellular domain, or affect highly conserved amino acid residues in the epidermal growth factor-like repeats of the protein. The affected cases represent diverse ethnic backgrounds and six come from traditionally consanguineous communities. In all affected subjects, the radiological phenotype is abnormal segmentation throughout the entire vertebral column with smooth outlines to the vertebral bodies in childhood, for which we suggest the term "pebble beach sign". This is a very consistent phenotype-genotype correlation and we suggest the designation SCD type 1 for the AR form caused by mutations in the DLL3 gene.

Detection of Jarcho-Levin syndrome at 12 weeks' gestation by nuchal translucency screening and three-dimensional ultrasound

Jarcho-Levin syndrome (JLS) or spondylothoracic dysotosis causes early newborn death from respiratory insufficiency. Prenatal diagnosis is possible using fetal ultrasound, but requires a high level of suspicion and definitive diagnosis may be delayed well into the second trimester. We present a case in which a combination of three-dimensional ultrasound and measurement of nuchal translucency thickness allowed successful detection of recurrent JLS at 12 weeks' gestation.

Mutations in the human delta homologue, DLL3, cause axial skeletal defects in spondylocostal dysostosis

Spondylocostal dysostosis (SD, MIM 277300) is a group of vertebral malsegmentation syndromes with reduced stature resulting from axial skeletal defects. SD is characterized by multiple hemivertebrae, rib fusions and deletions with a non-progressive kyphoscoliosis. Cases may be sporadic or familial, with both autosomal dominant and autosomal recessive modes of inheritance reported. Autosomal recessive SD maps to a 7.8-cM interval on chromosome 19q13.1-q13.3 that is homologous with a mouse region containing a gene encoding the Notch ligand delta-like 3 (Dll3). Dll3 is mutated in the X-ray-induced mouse mutant pudgy (pu), causing a variety of vertebrocostal defects similar to SD phenotypes. Here we have cloned and sequenced human DLL3 to evaluate it as a candidate gene for SD and identified mutations in three autosomal recessive SD families. Two of the mutations predict truncations within conserved extracellular domains. The third is a missense mutation in a highly conserved glycine residue of the fifth epidermal growth factor (EGF) repeat, which has revealed an important functional role for this domain. These represent the first mutations in a human Delta homologue, thus highlighting the critical role of the Notch signalling pathway and its components in patterning the mammalian axial

Genetics of the female reproductive ducts

Familial aggregates of the most common disorders of müllerian differentiation in females-Müllerian aplasia, incomplete Müllerian fusion-are best explained on the basis of polygenic/multifactorial inheritance. No information exists on the number and chromosomal location of responsible genes. Single mutant genes (Mendelian) are responsible for the McKusick-Kaufman syndrome (MKS) and the hand-foot-genital syndrome. The molecular basis for the latter condition involves HOXA13, but the molecular basis of MKS and other disorders of the female reproductive ducts is unknown. Vaginal atresia, Müllerian aplasia, and incomplete Müllerian fusion are not infrequently observed in malformation syndromes.

A gene for autosomal recessive spondylocostal dysostosis maps to 19q13.1-q13.3

In spondylocostal dysostosis (SD), vertebral-segmentation defects are associated with rib anomalies. This results in short-trunk short stature, nonprogressive kyphoscoliosis, and radiological features of multiple hemivertebrae and rib fusions. SD can be familial, and both autosomal dominant and autosomal recessive (AR) inheritance have been reported, but no genes have been identified or localized for nonsyndromic SD in humans. We performed genomewide scanning by homozygosity mapping in a large consanguineous ARSD Arab Israeli family with six definitely affected members. Significant linkage was found to chromosome 19q13, with a LOD score of 6.9. This was confirmed in a second Pakistani family with three affected members, with a LOD score of 2.4. The combined-haplotype data identify a critical region between D19S570 and D19S908, an interval of 8.5 cM on 19q13.1-19q13.3. This is the first study to localize a gene for nonsyndromic SD. ARSD is clinically heterogeneous and is likely to result from mutations in developmental genes or from regulating transcription factors. Identification of these genes will improve the understanding of the molecular processes contributing to both normal and abnormal human vertebral development.

Fetus with Casamassima-Morton-Nance syndrome and an inherited (6;9) balanced translocation

We report on a fetus with cranio-facial anomalies, a narrow thorax, imperforate anus with cloacal cyst, and a genitourinary malformation with absent uterus, vagina, and external genitalia. Major thoracic defects were seen on roentgenographic examination, including absent vertebrae and ribs, a supernumerary vertebra, a hemivertebra, and rib fusion. These findings are compatible with Casamassima-Morton-Nance syndrome. The patient was the carrier of a translocation t(6;9)(p12;q12), inherited from the mother. Although the occurrence of this rearrangement may be coincidental, it may also indicate a possible locus for this autosomal recessive thoracic dysplasia.

Jarcho-Levin syndrome associated with atrial septal defect and partial anomalous pulmonary venous return: a case report

A 61-year-old woman suffering from Jarcho-Levin syndrome (JLS) was associated with atrial septal defect and partial anomalous pulmonary venous return and underwent corrective surgery. Pressure controlled postoperative ventilator therapy is preferred in patients with JLS.

Multiple vertebral segmentation defects: analysis of 26 new patients and review of the literature

To further delineate and classify those forms of short trunk dwarfism characterized by multiple vertebral segmentation defects, we analyzed 26 new patients and reviewed 115 described in the literature. Three distinct entities were recognized based on radiographic and clinical findings. Jarcho-Levin syndrome is the lethal autosomal recessive form, characterized by a symmetric crab-like chest. Spondylocostal dysostosis is the benign autosomal dominant condition. Spondylothoracic dysostosis shows considerable clinical and radiographic overlap with spondylocostal dysostosis. Malformations observed in association with multiple vertebral segmentation defects are more common in the sporadic patients. Analysis of the 26 new individuals revealed that the body segment in which these nonvertebral malformations occur corresponds to the site of the vertebral segmentation defects.

Cerebrofaciothoracic syndrome

We report on a patient with a large septum pellucidum, hypodensity of gray matter, hypertelorism, and costovertebral anomalies. Only 5 previous cases have been described with this distinctive phenotype. Autosomal recessive inheritance seems likely.

Severe spondylocostal dysostosis associated with other congenital anomalies: a clinical/epidemiologic analysis and description of ten cases from the Spanish registry

We describe 10 cases born to nondiabetic mothers who presented with severe spondylocostal dysostosis (SCD) associated with other anomalies, identified among 20,526 malformed liveborn infants from the Spanish Collaborative Study of Congenital Malformations (ECEMC). We analyze the associated malformations in the 10 cases with severe SCD, as well as in all cases with less severe SCD among children with MCA patterns of unknown cause. Cases with SCD were preferentially associated with caudal dysgenesis, diaphragmatic hernia, and central nervous system anomalies.

Segmentation anomalies of the vertebras and ribs: a developmental field defect: epidemiologic evidence

Opitz has defined developmental field defects (DFD) as "any dysmorphogenetically reactive unit of the developing organism that leads to final structure." We have incorporated in our coding system specific codes to identify individual DFDs in each child, irrespective of the cause or type of the MCA pattern (i.e., chromosomal, mendelian, environmental, or unknown). Using this approach, we can analyze the group of defects included in the expression of each DFD as a discrete unit. To confirm our hypothesis that vertebral and rib anomalies constitute a DFD, we have studied all of our cases with segmentation anomalies of the spine and ribs, including hemivertebrae, fused or absent vertebrae, and "crab-like" thorax, all of which fall into the loosely defined groups of spondylothoracic dysplasia, costovertebral dysplasia, Jarcho-Levin syndrome, and others. The study was performed using the 18,743 malformed children from the ECEMC data files, 110 of them having vertebral/rib anomalies.

Multiple pterygium syndrome with body asymmetry

We report on a fetus with multiple pterygia in the popliteal, antecubital, intercrural, axillary, and nuchal region, arthrogryposis, camptodactyly, anal atresia, hypospadias, ambiguous genitalia, and neonatal death. Arthrogryposis was much more pronounced at the left than at the right side. Moreover, there was gross body asymmetry with hypoplasia of the left arm, leg, pelvis, and kidney. As this spectrum of anomalies does not fit any of the known multiple pterygium syndromes, this patient adds another clinical entity to the already wide spectrum of multiple pterygium syndromes.

Spondylothoracic dysplasia (Jarcho-Levin syndrome) in a Chinese baby

Spondylothoracic dysplasia (STD) syndrome or the Jarcho-Levin syndrome has been seen commonly in Puerto Ricans. A case of STD syndrome in a Chinese baby which we believe is the first reported case in an Asian baby is reported. The skeletal disorder syndrome affecting the spine, ribs and thorax is an autosomal recessive disorder with associated non-skeletal anomalies. It should not be confused with the phenotypically similar skeletal disorder known as spondylocostal dysplasia, which is an autosomal dominant disease.

Case of multivertebral anomalies, cloacal dysgenesis, and other anomalies presenting prenatally as cystic kidneys

We describe a newborn boy on whom prenatal ultrasonography demonstrated intrauterine growth retardation, multiple vertebral anomalies, cystic kidneys, and oligohydramnios. Autopsy findings included multiple vertebral anomalies, cloacal dysgenesis (imperforate anus, vesicorectal fistula, and bilateral renal dysplasia), sacral absence, single umbilical artery, pulmonary hypoplasia, scoliosis, and hexadactyly of the left thumb. Although our case resembles a previously described case, a definitive diagnosis could not be made. The differential diagnosis included a variant of spondylocostal dysostosis and the VATER association.

Congenital synspondylism

We present 3 patients with a specific pattern of congenital familial extensive vertebral anomalies (CFEVA) with vertebral and carpal coalition. It is proposed that these patients and two previously reported cases have a vertebral disorder akin to symphalangism in the fingers. The name synspondylism is proposed. Two instances of sib recurrence point to Mendelian segregation in some instances of synspondylism. The syndromes and associations encompassed by CEFVA are reviewed. The clinical and radiographic manifestations of congenital synspondylism are discussed in the perspective of the possible pathogenesis of segmentation disorders of the spine.

Jarcho-Levin syndrome: four new cases and classification of subtypes

The Jarcho-Levin syndrome is a condition manifested by vertebral body and related rib malformations. We report on four new cases and review 57 cases from the literature. Analysis of the 61 cases suggests that there are two major subtypes (spondylocostal dysostosis and spondylothoracic dysostosis) with different survival rates, associated malformations, and inheritance patterns. Individuals with spondylothoracic dysostosis have vertebral body malformations and ribs which flare in a fanlike pattern but which are not significantly malformed. This is an autosomal recessive trait, and the patients have a higher mortality rate and greater incidence of neural tube defects. Individuals with spondylocostal dysostosis have vertebral malformations, frequent dramatic rib malformations, and short stature, but do not have a fanlike thoracic configuration. Most cases of spondylocostal dysostosis are inherited in an autosomal recessive fashion, although in a few families it is a dominant trait which is correlated with better survival. Respiratory compromise previously accounted for the high mortality in these conditions, but improvements in respiratory technology have increased survival. Appropriate classification of these similar phenotypes will improve counseling concerning recurrence risk, management, and prognosis.

Familial Jarcho-Levin syndrome

Jarcho-Levin syndrome is a variety of autosomal recessive spondylocostal dysostosis characterized by severe deformity of the thoracic cage, leading to respiratory failure and early death. There are often associated dysmorphic features. The disease is more frequent in Puerto Ricans and rare in Europe. A Sicilian family with four affected individuals in two interrelated sibships is reported.

Evidence for variable gene expression in a large inbred kindred with autosomal recessive spondylocostal dysostosis

Seven members of a large inbred kindred with autosomal recessive spondylocostal dysostosis were examined clinically, radiographically, and sonographically. The subjects were three adults, one adolescent, and three children under 3 years of age. One child was the offspring of a first cousin marriage which showed quasi-dominant inheritance. Six subjects had short stature owing to widespread vertebral dyssegmentation with variable reduction in rib number and rib fusion. One subject was of normal stature, had limited vertebral dyssegmentation, an extra rib, and no rib fusion. Five subjects showed the plagiocephaly-torticollis sequence. Four of the five male subjects had inguinal herniation on one or both sides. All subjects had normal renal ultrasonography. The youngest subject died of cardiopulmonary complications and is thought to represent one extreme in the expressivity of the gene in this kindred.

Spondylocostal dysostosis: dominant type

We report on a father and daughter who have spondylocostal dysostosis. The girl's ribs are more severely abnormal than those of the 2 previously reported cases of dominant spondylocostal dysostosis and are rather suggestive of the autosomal recessive type. The differential diagnosis of both forms is discussed.

Spondylocostal dysostosis: an example of autosomal dominant transmission in a large family

This report gives a description of a three-generation family in which spondylocostal dysostosis associated with previously unreported neurological complaints occurred in five family members, suggesting autosomal dominant inheritance. A review of the literature is presented and previously unreported neurological complaints, e.g. neurogenic claudicatio, are emphasized.

Inherited diseases in North American Mennonites: focus on Old Colony (Chortitza) Mennonites

The patterns of migration and the genetic disorders occurring among North American Mennonites are reviewed, and inherited conditions recently recognized in a religious and genetic isolate, the Old Colony (Chortitza) Mennonites, are described. Old Colony Mennonites are of Dutch/German origin and descend from approximately 400 founding families who settled in the Old Colony, Chortitza (the Ukraine, USSR) in the late 1700s, and then migrated to Canada and Central and South America in the past century. We investigated over 6 generations of a Canadian Old Colony kindred in which there was extensive intermarriage, and in whom 28 individuals developed diabetes mellitus. Insulin-dependent diabetes mellitus (IDDM) occurred in 14 affected individuals in 10 closely related sibships; the 11 living IDDM patients were all concordant for the immunogenetic marker HLA-DR4. Fourteen close relatives had other disorders of carbohydrate metabolism, including gestational diabetes and non-insulin-dependent diabetes mellitus. Other close relatives had autoimmune diseases, including rheumatoid arthritis, hyper- and hypothyroidism, multiple sclerosis, and red cell aplasia. Other inherited diseases, including Alport syndrome, congenital defects, and inborn errors of metabolism were also found in the kindred. In the almost exclusively (99%) Old Colony Mennonite public health district in which the kindred was ascertained, there were multiple cases of Tourette syndrome, of malformations (including congenital heart defects and cleft lip +/- palate), and familial clusters of inborn errors of metabolism. We report this Old Colony (Chortitza) Mennonite isolate because 1) there are large familial aggregations of tissue-specific autoimmune diseases, malformations, inborn errors of metabolism, and of some other conditions whose genetic basis is still unknown; 2) there are multiple cases of rare genetic conditions, 3) we have established a computerized genealogic data base on over 1,000 kindred members as well as a cryopreserved lymphocyte/DNA bank on over 100 closely related individuals with various genetic conditions; and 4) this religious isolate, which extends across North, Central, and South America, offers an excellent opportunity for studying the epidemiology and molecular genetics of both common and rare inherited diseases.