Roberts'--SC phocomelia syndrome with cytogenetic findings

Long-term survival after corrective surgeries in two patients with severe deformities due to Roberts syndrome: A Case report and review of the literature

Roberts syndrome (RBS; OMIM 268300) is a rare autosomal recessive disease characterized by retardation before and after birth, cranial and maxillofacial deformities, limb anomalies and intellectual disability. Mutations in the establishment of cohesion 1 homologue 2 (ESCO2) gene on chromosome 8p21.1 have been found to be causative for RBS. We describe two patients with RBS with physical deformities and ll. One is an 8-year-old Yemeni male, and the other is his 13-year-old sister. These patients were diagnosed with RBS and underwent surgeries during their first to third years of life. Here, we present the cases for the two patients, focusing specifically on their surgical management and outcomes. Additionally, by reviewing the literature on RBS, we also summarize the proper surgical interventions for this rare disease. This paper describes the long-term follow-up of two patients with severe deformities who benefitted from corrective surgeries. The findings of this study indicate that patients who survive infancy and reach adulthood, even patients who present with severe disease symptoms, can benefit from corrective surgeries and lead better lives.

Roberts syndrome: a review of 100 cases and a new rating system for severity

Roberts syndrome (RS) is a rare genetic disorder characterized by pre- and postnatal growth retardation, limb defects, and craniofacial anomalies. Affected persons have varying degrees of malformations involving symmetric reduction in the number of digits, and length or presence of bones in the arms and legs. Craniofacial malformations involve hypertelorism, hypoplastic nasal alae, and a high incidence of cleft lip and palate. Familial and sporadic cases have been reported consistent with an autosomal recessive mode of inheritance. Mitotic cells from many individuals with RS display a characteristic cytogenetic phenomenon consisting of repulsion of heterochromatic regions near centromeres, particularly of chromosomes 1, 9, 16, and splaying of the short arms of the acrocentrics and of the distal Yq. Mitosis in RS cells is abnormal in metaphase duration and anaphase progression. Specifically, anaphase figures show a higher degree of chromosomes that are outlying, lagging, or prematurely advancing toward the poles compared to normal controls. RS cells have abnormal nuclear morphology and also show a higher frequency of micronucleation than normal cells, presumably as a result of the abnormal mitotic events during anaphase. Therefore, RS has been interpreted as a human mitotic mutation syndrome which leads to secondary developmental defects. This report reviews 100 cases of RS, summarizes the phenotypic, genetic, cytogenetic, and cell biology findings in Roberts syndrome, and introduces the RS Rating for quantitating severity.

A sibship with Roberts/SC phocomelia syndrome

We report on a family in which 3 sibs have Roberts/SC phocomelia syndrome. One child has survived to age 9 years. The clinical manifestations and the natural history of this syndrome are reviewed.

Roberts syndrome and SC phocomelia. A single genetic entity

A family with three siblings showing different manifestations of Roberts syndrome or SC phocomelia is described. With regard to previously published cases of familial Roberts syndrome and SC phocomelia we conclude that these two syndromes are one and the same genetic entity.

SC phocomelia syndrome, premature centromere separation, and congenital cranial nerve paralysis in two sisters, one with malignant melanoma

Two middle age sisters had most manifestations of the SC phocomelia syndrome including postnatal growth retardation, symmetric limb deficiencies with radial aplasia and absent thumbs, facial anomalies with microcephaly, microphthalmia, hypoplastic nasal alae, and borderline to mild mental retardation. Unusual findings included congenital paralysis of some cranial nerves in both patients and malignant melanoma in the proposita. Cultured lymphocytes from both patients, and skin fibroblasts, Epstein Barr virus-transformed lymphocytes, and tumor cells from the proposita demonstrated premature separation of centromeric heterochromatin (PCS) of many chromosomes, a finding noted previously in the SC phocomelia syndrome and the similar but more severe Roberts syndrome. Extensive overlap of the phenotypes of the sisters and 15 other patients with either syndrome and PCS confirms that these are either allelic conditions or the same disease--designated Roberts-SC phocomelia syndrome. The role of PCS in the syndrome(s) remains uncertain since some patients with the characteristic clinical phenotypes are reported to lack it.

Premature centromere splitting in a presumptive mild form of Roberts syndrome

Cytogenetic investigations performed on lymphocytes from a 29-year-old woman with no severe anomalies, allowed us to recognize a mild form of Roberts syndrome. The proposita's metaphases showed a consistent centromere splitting, especially affecting chromosomes 16, 19, 21, and 22. This centromere separation sequence seems to be unique to Roberts syndrome cells. The experiments also showed that no diffusible factor, involved in the mechanism of sister chromatid pairing-disjunction, exists.