Autosomal recessive Leber's hereditary optic neuropathy caused by a homozygous variant in DNAJC30 gene

Recently, Stenton et al. (2021) described a new, autosomal recessive inheritance pattern of Leber's hereditary optic neuropathy (LHON) caused by missense variants in the DNAJC30 gene. The DNAJC30 c.152A > G, p.(Tyr51Cys) variant was by far the most common variant reported in patients originating from Eastern Europe, therefore, it is believed to be a founder variant in these populations. We report the first two cases of DNAJC30-linked autosomal recessive LHON in a young male and a female originating from Estonia. The patients presented severe loss of central vision and clinical features indistinguishable from mitochondrial LHON. The whole exome sequencing carried out in the male patient and the next-generation sequencing panel in the young female patient identified the same homozygous missense variant in the DNAJC30 gene. Our cases further reinforce the pathogenicity of c.152A > G, p.(Tyr51Cys) DNAJC30 variant causing autosomal recessive LHON. According to the gnomAD database, the allele frequency of this variant in the Estonian population is 0.8%, translating into a prevalence of carriers of 1:60. It is the highest among different gnomAD populations. Applying the Hardy-Weinberg equation, an estimated 92 persons in the Estonian population carry the homozygous variant c.152A > G, p.(Tyr51Cys) in DNAJC30. In patients with LHON, we advise sequencing both the DNAJC30 gene and mitochondrial DNA simultaneously.

Guidelines for the Diagnosis and Treatment of Pediatric Familial Hypercholesterolemia 2022

As atherosclerosis begins in childhood, early diagnosis and treatment of familial hypercholesterolemia (FH) is considered necessary. The basic diagnosis of pediatric FH (under 15 years of age) is based on hyper-low-density lipoprotein (LDL) cholesterolemia and a family history of FH; however, in this guideline, to reduce overlooked cases, "probable FH" was established. Once diagnosed with FH or probable FH, efforts should be made to promptly provide lifestyle guidance, including diet. It is also important to conduct an intrafamilial survey, to identify family members with the same condition. If the level of LDL-C remains above 180 mg/dL, drug therapy should be considered at the age of 10. The first-line drug should be statin. Evaluation of atherosclerosis should be started using non-invasive techniques, such as ultrasound. The management target level is an LDL-C level of less than 140 mg/dL. If a homozygous FH is suspected, consult a specialist and determine the response to pharmacotherapy with evaluating atherosclerosis. If the response is inadequate, initiate lipoprotein apheresis as soon as possible.

Does selection occur at the intermediate zone of two insufficiently isolated populations? A whole-genome analysis along an altitudinal gradient

Adaptive divergence occurs even between insufficiently isolated populations when there is a great difference in environments between their habitats. Individuals present in an intermediate zone of the two divergent populations are expected to have an admixed genetic structure due to gene flow. A selective pressure that acts on the genetically admixed individuals may limit the gene flow and maintain the adaptive divergence. Here, we addressed a question whether selection occurs in the genetically admixed individuals between two divergent populations. Arabidopsis halleri is a perennial montane plant, which has clear phenotypic dimorphisms between highland and lowland habitats in Mt. Ibuki, central Japan. We obtained the whole-genome sequences of Arabidopsis halleri plants along an altitudinal gradient of 359-1,317 m with a high spatial resolution (mean altitudinal interval of 20 m). We found a zone where the highland and lowland genes were mixing (intermediate subpopulation). In the intermediate subpopulation, we identified 5 and 13 genome regions, which included 3 and 8 genes, that had a high frequency of alleles that are accumulated in highland and lowland subpopulations, respectively. In addition, we also found that the frequency of highland alleles of these selected genome regions was smaller in the lowland subpopulation compared with that of the non-selected regions. These results suggest that the selection in the intermediate subpopulation might limit the gene flow and contribute to the adaptive divergence between altitudes. We also identified 7 genome regions that had low heterozygote frequencies in the intermediate subpopulation. We conclude that different types of selection in addition to gene flow occur at the intermediate altitude and shape the genetic structure across altitudes.

A high-efficiency and versatile CRISPR/Cas9-mediated HDR-based biallelic editing system

Clustered regulatory interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 nuclease (Cas9), the third-generation genome editing tool, has been favored because of its high efficiency and clear system composition. In this technology, the introduced double-strand breaks (DSBs) are mainly repaired by non-homologous end joining (NHEJ) or homology-directed repair (HDR) pathways. The high-fidelity HDR pathway is used for genome modification, which can introduce artificially controllable insertions, deletions, or substitutions carried by the donor templates. Although high-level knock-out can be easily achieved by NHEJ, accurate HDR-mediated knock-in remains a technical challenge. In most circumstances, although both alleles are broken by endonucleases, only one can be repaired by HDR, and the other one is usually recombined by NHEJ. For gene function studies or disease model establishment, biallelic editing to generate homozygous cell lines and homozygotes is needed to ensure consistent phenotypes. Thus, there is an urgent need for an efficient biallelic editing system. Here, we developed three pairs of integrated selection systems, where each of the two selection cassettes contained one drug-screening gene and one fluorescent marker. Flanked by homologous arms containing the mutated sequences, the selection cassettes were integrated into the target site, mediated by CRISPR/Cas9-induced HDR. Positively targeted cell clones were massively enriched by fluorescent microscopy after screening for drug resistance. We tested this novel method on the amyloid precursor protein (APP) and presenilin 1 (PSEN1) loci and demonstrated up to 82.0% biallelic editing efficiency after optimization. Our results indicate that this strategy can provide a new efficient approach for biallelic editing and lay a foundation for establishment of an easier and more efficient disease model.

Association between RNF213 c.14576G>A Variant (rs112735431) and Peripheral Pulmonary Artery Stenosis in Moyamoya Disease

BACKGROUND

Moyamoya disease (MMD) and peripheral pulmonary artery stenosis (PPAS) are relatively rare and demonstrate steno-occlusive vascular lesions in different organs. Genetic studies identified RNF213 polymorphism c.14576G>A (rs112735431) as a susceptibility variant for East Asian MMD. RNF213 polymorphism c.14576G>A is further associated with various vascular lesions of other organs. In this study, we aimed to clarify the incidence and clinical manifestations of PPAS in MMD patients and analyze the correlation between RNF213 genotype and PPAS.

METHODS

This retrospective case-control study investigated the association between RNF213 polymorphism and PPAS in 306 MMD/quasi-MMD patients, reviewing the medical charts and imaging records of consecutive patients with MMD admitted from January 2015 to December 2020.

RESULTS

PPAS was observed in 3 MMD/quasi-MMD patients (0.98%, 3/306). RNF213 polymorphism c.14576G>A was determined for all 306 MMD/quasi-MMD patients. The incidence of PPAS in RNF213-wildtype, RNF213-heterozygote, and RNF213-homozygote MMD/quasi-MMD patients was 0% (0/101), 0.5% (1/200), and 40% (2/5), respectively. The association between PPAS and homozygote polymorphism of RNF213 c.14576G>A was statistically significant in MMD/quasi-MMD patients (p = 0.0018). In all cases, pulmonary artery hypertension due to PPAS was evident during their childhood and young adolescent stages. Surgical indications for MMD were discouraged in 1 case due to her severe cardiopulmonary dysfunction.

CONCLUSIONS

The homozygote variant of RNF213 polymorphism c.14576G>A can be a potential predisposing factor for PPAS in MMD/quasi-MMD patients. Despite the relatively rare entity, PPAS should be noted to determine surgical indications for MMD/quasi-MMD patients.

Homozygous Germline APC p.I1307K Variants: A Case Series

Approximately 10% of all colorectal cancer is estimated to be due to an inherited predisposition. Identification of a germline pathogenic variant can aid in treatment, screening, and surveillance and help stratify familial cancer risks based on gene-specific cancer associations. The APC gene contributes to a small percentage of hereditary colon cancer, with most pathogenic APC variants causing familial adenomatous polyposis syndrome. However, one specific variant in APC called p.I1307K, found in approximately 10% of Ashkenazi Jewish individuals, is associated with a moderate risk for colon cancer, but not polyposis. Heterozygous carriers of one p.I1307K variant are well documented in the literature, and guidelines recommend earlier and more frequent colonoscopies. Conversely, reports of homozygous carriers of 2 p.I1307K variants are limited, and guidelines for medical management are lacking. This case series describes 4 homozygous p.I1307K patients of Ashkenazi Jewish ancestry identified in cancer genetics clinics. Case 1 is a 73-year-old pancreatic cancer patient with a family history of melanoma and colon cancer. Case 2 is a 62-year-old patient with a personal history of 4 adenomatous colorectal polyps and a family history of breast, pancreatic, colon, and prostate cancers. Case 3 is a 52-year-old patient with a personal history of early-onset breast cancer and uveal melanoma and a family history of breast, prostate, and stomach cancers. Case 4 is a 70-year-old patient with a personal history of gallbladder adenocarcinoma and a family history of breast cancer. These cases exhibit wide phenotypic variability and contribute to the limited reports of homozygous p.I1307K variant carriers.

A case of Huntington's disease with two reduced penetrance alleles

We present a case of Huntington's Disease (HD) with two reduced penetrance alleles and show that age of onset and motor symptoms are comparable to heterozygous patients with the same number of CAG triplet repeats. We performed a review of the literature on clinical presentation of homozygous HD cases and highlight that, so far, evidence exists that HD is a truly dominant disorder. This has important implications for pathophysiology concepts of the disease.

Doubled Haploid Broccoli (Brassica olearacea var. italica) Plants from Anther Culture

Broccoli (Brassica olearecea var. italica) is a cole crop grown for its floral heads and stalks. It is rich in bioactive chemicals good for human health. Broccoli has been consumed as a vegetable since Roman times, but its production and consumption have increased significantly over the past few decades. Breeders try to develop new broccoli varieties with high yield, improved quality, and resistance to biotic and abiotic stresses. Almost all new broccoli varieties are F1 hybrids. Development of inbred broccoli lines that can be used as parents in hybrid production is a time-consuming and difficult process. Haploidization techniques can be utilized as a valuable support in broccoli breeding programs to speed up the production of genetically pure genotypes. Haploid plants of broccoli can be produced from immature male gametophytes via anther and microspore cultures with similar success rates. The most important parameters affecting the success of haploidization in broccoli are the genetic background (genotype) and the developmental stage of the microspores. Broccoli genotypes differ in their responses to androgenesis induction. The highest androgenesis response could be induced from microspores in late uninucleate and early binucleate stages. Recovery of diploid broccoli plants from haploids is possible via spontaneous and induced doubling. Doubled haploid (DH) broccoli lines are considered to be fully homozygous. Therefore, the production of DH lines is an alternative way to obtain pure inbred lines that can be utilized as parents in the development of new F1 hybrid varieties showing high levels of heterosis, high-quality heads, and uniform harvestable crop. We are using an anther culture-based haploid plant production system to develop DH broccoli lines in our broccoli breeding program. DH broccoli lines are produced from different genetic backgrounds within a year and handed to broccoli breeders.

Effect of Point Mutation in the Growth Differentiation Factor 9 Gene of Oocytes on the Sterility and Fertility of Awassi Sheep

Growth differentiation factor 9 (GDF9) plays a critical role in ovarian follicular development and ovulation rate. The present study aimed to investigate the correlation between the single-nucleotide polymorphism (SNP) of the GDF9 gene and reproductive performance variables, such as fertility and sterility in Awassi sheep. Forty pairs of ovaries from a total of 40 slaughtered Iraqi Awassi ewes were used in this study. Twenty of the ovaries were collected from sterile ewes and the other 20 ovaries were taken from fertile ewes for genomic DNA extraction, polymerase chain reaction, and sequencing to detect GDF9 gene polymorphism. Follicles and oocytes of all the 40 ovaries were evaluated and compared with the results of genotyping. Furthermore, histopathological and microscopic evaluations were performed for 40 ovarian tissues of the two groups. The sequence analysis revealed that exon I had three SNPs, including T(114)C, G(129)R, and G(199)A. The first two SNPs were silent mutations and the last mutation was missense responsible for the substitution of glutamic acid with lysine at position 67. The current study showed a significant increase (P≤0.01) in GG, AA, CC, GA, and GG genotypes at G(129)R, G(199)A, T(114)C, G(129)R, and G(199)A loci, respectively. Moreover, the TT genotype in locus T(114)C was recorded to significantly augment (P≤0.05) in the fertile ewes. Mutant GA genotype of the G(129)R locus led to a significant (P≤0.05) increase in the percentage of follicles (4-8 mm) and oocytes number, compared to wild GG. On the other hand, a significant decrease was recorded in the mutant AA genotype in G(199)A, compared to wild GG. Differences between CC and TT genotypes at T(114)C locus were not significant. Histopathological examination revealed hypoplasia in the ovarian tissue of sterile ewes accompanied by fibrous connective tissue invasion and follicles degeneration. However, in the fertile ewes, the ovarian tissues were normal with the presence of numerous corpus albicans and degenerative corpus luteum. According to the findings of this study, the homozygote mutation in fertile ewes minimized the number of follicles and oocytes leading to sterility, while the heterozygote mutation was reported in the fertile Awassi ewes.

A histopathological report of a 16-year-old male with peripheral pulmonary artery stenosis and Moyamoya disease with a homozygous RNF213 mutation

Peripheral pulmonary artery stenosis (PPAS) is a rare pulmonary vasculopathy characterized by multiple stenoses and obstructions in the peripheral pulmonary arteries. PPAS often develops in children with congenital diseases such as Williams syndrome and Alagille syndrome; however, recent studies have reported PPAS cases in adults with Moyamoya disease (MMD). Recent genetic studies have demonstrated that ring finger protein 213 (RNF213) is a susceptibility gene for MMD. However, the pathophysiology of combined PPAS and MMD and the relationship between the two diseases remain largely unknown. Here we report a case of PPAS in a 16-year-old male, with a history of MMD, who died suddenly at 24. An autopsy was performed, and remarkable pathological changes were identified in the pulmonary arteries and in other arteries. Furthermore, genetic analysis revealed that the patient had a homozygous c.14576G > A (p.R4859K) mutation in RNF213. This is the first report to demonstrate the histopathology of systemic arteriopathy in a case with MMD and PPAS with a confirmed homozygous RNF213 mutation. We also review immunohistochemical data from the case and discuss how RNF213 mutation could have resulted in the observed vascular abnormalities.

Homozygosity for the A431E mutation in PSEN1 presenting with a relatively aggressive phenotype

OBJECTIVE

We report a 35 year-old male with childhood learning disability and early onset dementia who is homozygous for the A431E variant in the PSEN1 gene. Presenilin1 mutations are associated with autosomal dominant Alzheimer's dementia with young and somewhat stereotyped onset. Such variants may cause Alzheimer's dementia through aberrant processing of amyloid precursor protein through effects on γ-secretase activity. γ-secretase is involved in the cleavage of many proteins critical to normal function, including brain development. Therefore, manifestations in persons without normal Presenilin1 function is of interest.

METHODS

Clinical evaluation including family history, examination, brain MRI, and genetic analysis.

RESULTS

Our patient had mild developmental delay, chronic nighttime behavioral disturbance, and onset of progressive cognitive deficits at age 33. Clinical evaluation demonstrated spastic paraparesis and pseudobulbar affect. Brain MRI revealed cerebral atrophy disproportionate to age. Chronic microhemorrhages within bilateral occipital, temporal, and right frontal lobes were seen. Sanger sequencing confirmed homozygosity for the A431E variant in PSEN1, which is a known pathogenic variant causing autosomal dominant Alzheimer's dementia.

CONCLUSIONS

Our report demonstrates that homozygosity for pathogenic Presenilin1 variants is compatible with life, though may cause a more aggressive phenotype with younger age of onset and possibly REM behavior disorder.

Efficient Production of Biallelic RAG1 Knockout Mouse Embryonic Stem Cell Using CRISPR/Cas9

Background

Recombination Activating Genes (RAG) mutated embryonic stem cells are (ES) cells which are unable to perform V (D) J recombination. These cells can be used for generation of immunodeficient mouse. Creating biallelic mutations by CRISPR/Cas9 genome editing has emerged as a powerful technique to generate site-specific mutations in different sequences.

Objectives

The main purposes of this study were to achieve complete knock-out of RAG1 gene by investigating the nature of mutations in mutant mESC and to generate RAG1 knock-out mESCs containing homozygous indels with the aim of creating desired and specific RAG-1 -/- mutant mouse in a shorter period of time.

Materials and Methods

Here, we first utilized CRISPR/Cas9 system to target RAG1/RAG2 genes in NIH3T3 cells to test the activity and efficiency of our CRISPR system. Then we used the system for targeting RAG1 gene in mouse embryonic stem cell (mESCs) to generate knock-out embryonic stem cells. This method combined with highly active single guide RNA (sgRNA) is an efficient way to produce new RAG1-knockout mESCs in the selected regions of early coding DNA sequence, approximately between nucleotide c. 512-c. 513 and nucleotide c. 725-c. 726 of RAG1 coding sequence that had not been targeted previously.

Results

CRISPR gene editing resulted in a multitude of engineered homozygous and compound heterozygous mutations, including both in-frame and out-of-frame indels in 92% of mES cell clones. Most of the mutations generated by CRISPR/Cas9 system were out-of-frame, resulting in a complete gene knockout. In addition, 59% of the mutant ES cell clones carried out-of-frame homozygous indel mutations. The RAG1-knockout mESC clones retained normal morphology and pluripotent gene expression.

Conclusions

Our study demonstrated that CRISPR/Cas9 system can efficiently create biallelic indels containing both homozygous and compound heterozygous RAG1 mutations in about 92% of the mutant mESC clones. The 59% of mutant ES cell clones carried out-of-frame homozygous indel mutations.

Guidelines for Diagnosis and Treatment of Familial Hypercholesterolemia 2017

Statement1. Familial hypercholesterolemia (FH) is an autosomal hereditary disease with the 3 major clinical features of hyper-LDL-cholesterolemia, premature coronary artery disease and tendon and skin xanthomas. As there is a considerably high risk of coronary artery disease (CAD), in addition to early diagnosis and intensive treatment, family screening (cascade screening) is required (Recommendation level A) 2. For a diagnosis of FH, at least 2 of the following criteria should be satisfied:① LDL-C ≥180 mg/dL, ② Tendon/skin xanthomas, ③ History of FH or premature CAD within 2nd degree blood relatives (Recommendation level A) 3. Intensive lipid-lowering therapy is necessary for the treatment of FH. First-line drug should be statins. (Recommendation level A, Evidence level 3) 4. Screening for CAD as well as asymptomatic atherosclerosis should be conducted periodically in FH patients. (Recommendation level A) 5. For homozygous FH, consider LDL apheresis and treatment with PCSK9 inhibitors or MTP inhibitors. (Recommendation level A) 6. For severe forms of heterozygous FH who have resistant to drug therapy, consider PCSK9 inhibitors and LDL apheresis. (Recommendation level A) 7. Refer FH homozygotes as well as heterozygotes who are resistant to drug therapy, who are children or are pregnant or have the desire to bear children to a specialist. (Recommendation level A).

Guidance for Pediatric Familial Hypercholesterolemia 2017

This paper describes consensus statement by Joint Working Group by Japan Pediatric Society and Japan Atherosclerosis Society for Making Guidance of Pediatric Familial Hypercholesterolemia (FH) in order to improve prognosis of FH.FH is a common genetic disease caused by mutations in genes related to low density lipoprotein (LDL) receptor pathway. Because patients with FH have high LDL cholesterol (LDL-C) levels from the birth, atherosclerosis begins and develops during childhood which determines the prognosis. Therefore, in order to reduce their lifetime risk for cardiovascular disease, patients with FH need to be diagnosed as early as possible and appropriate treatment should be started.Diagnosis of pediatric heterozygous FH patients is made by LDL-C ≥140 mg/dL, and family history of FH or premature CAD. When the diagnosis is made, they need to improve their lifestyle including diet and exercise which sometimes are not enough to reduce LDL-C levels. For pediatric FH aged ≥10 years, pharmacotherapy needs to be considered if the LDL-C level is persistently above 180 mg/dL. Statins are the first line drugs starting from the lowest dose and are increased if necessary. The target LDL-C level should ideally be ＜140 mg/dL. Assessment of atherosclerosis is mainly performed by noninvasive methods such as ultrasound.For homozygous FH patients, the diagnosis is made by existence of skin xanthomas or tendon xanthomas from infancy, and untreated LDL-C levels are approximately twice those of heterozygous FH parents. The responsiveness to pharmacotherapy should be ascertained promptly and if the effect of treatment is not enough, LDL apheresis needs to be immediately initiated.

Homozygote of spinocerebellar Ataxia type 3 correlating with severe phenotype based on analyses of clinical features

BACKGROUND

Spinocerebellar ataxia type 3 (SCA3) is the most common subtype of SCAs worldwide. SCA3 homozygote is defined as expanded CAG repeats in both alleles that might exhibit severe phenotype due to gene dosage effect. However, a study on the systematic comparison of clinical phenotypes between homozygotes and heterozygotes to indicate these verity of phenotypes of homozygotes is still lacking.

METHODS

A total of 14 SCA3 homozygotes (3 Chinese participants and 11 participants from various ethnicity in different published studies) and 143 Chinese heterozygotes of SCA3 were recruited for this study. The 95% confidence intervals (CIs) of age at onset and disease severity expected from heterozygous patients were analyzed to detect the phenotypic differences between homozygotes and heterozygotes.

RESULTS

Almost all the homozygotes (13 of 14) were found to present a significant earlier age at onset compared with heterozygotes, because age at onset of most homozygotes was lower than the 95% CIs of age at onset of heterozygotes. Also, the clinical severity in most of the homozygotes (3 of 4) with identified clinical phenotypes was higher than the 95% CIs of severity in heterozygotes, indicating more severe clinical phenotypes in SCA3 homozygotes.

CONCLUSIONS

The homozygosity for SCA3 could lead to an earlier age of onset and putative severe clinical features. The findings of the present study suggested an influence of gene dosage on SCA3 phenotypes.

Phenotypic Spectrum of Children with Nephronophthisis and Related Ciliopathies

BACKGROUND AND OBJECTIVES

Genetic heterogeneity and phenotypic variability are major challenges in familial nephronophthisis and related ciliopathies. To date, mutations in 20 different genes (NPHP1 to -20) have been identified causing either isolated kidney disease or complex multiorgan disorders. In this study, we provide a comprehensive and detailed characterization of 152 children with a special focus on extrarenal organ involvement and the long-term development of ESRD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We established an online-based registry (www.nephreg.de) to assess the clinical course of patients with nephronophthisis and related ciliopathies on a yearly base. Cross-sectional and longitudinal data were collected. Mean observation time was 7.5±6.1 years.

RESULTS

In total, 51% of the children presented with isolated nephronophthisis, whereas the other 49% exhibited related ciliopathies. Monogenetic defects were identified in 97 of 152 patients, 89 affecting NPHP genes. Eight patients carried mutations in other genes related to cystic kidney diseases. A homozygous NPHP1 deletion was, by far, the most frequent genetic defect (n=60). We observed a high prevalence of extrarenal manifestations (23% [14 of 60] for the NPHP1 group and 66% [61 of 92] for children without NPHP1). A homozygous NPHP1 deletion not only led to juvenile nephronophthisis but also was able to present as a predominantly neurologic phenotype. However, irrespective of the initial clinical presentation, the kidney function of all patients carrying NPHP1 mutations declined rapidly between the ages of 8 and 16 years, with ESRD at a mean age of 11.4±2.4 years. In contrast within the non-NPHP1 group, there was no uniform pattern regarding the development of ESRD comprising patients with early onset and others preserving normal kidney function until adulthood.

CONCLUSIONS

Mutations in NPHP genes cause a wide range of ciliopathies with multiorgan involvement and different clinical outcomes.

Association of cytokine gene polymorphisms (IL‑6, IL‑12B, IL‑18) with Behcet's disease : A meta-analysis

PURPOSE

This study aims to investigate the association of cytokine gene polymorphisms with the risk of Behcet's disease (BD) via comprehensive meta-analysis.

METHODS

The Embase and PubMed databases covering the period from the earliest possible year to May 2015 were searched. A total of 13 eligible articles including 2,065 BD patients and 1,559 controls were recruited. Odds ratios (ORs) and 95 % confidence intervals (CIs) were used to assess the strength of the associations. Potential publication bias was evaluated using Egger's linear regression test.

RESULTS

Meta-analysis indicated associations between IL‑6 rs1800795, IL‑12B rs3212227, and IL‑18 rs1946518 in all study subjects: IL‑18 rs1946518 in the dominant model (IL‑18 rs1946518: OR = 0.48, 95 % CI: 0.34-0.70, P = 0.000) and the homozygote model (IL‑18 rs1946518: OR = 0.40, 95 % CI: 0.25-0.65, P = 0.000); and IL‑6 rs1800795 and IL‑12B rs3212227 in the dominant model (IL‑6 rs1800795: OR = 0.53, 95 % CI: 0.39-0.72, P = 0.000; IL‑12B rs3212227: OR = 1.26, 95 % CI: 1.06-1.48, P = 0.007; IL‑18 rs1946518: OR = 0.46, 95 % CI: 0.33-0.65, P = 0.000). No significant evidence for associations of IL‑18 rs187238 polymorphisms with BD susceptibility was detected.

CONCLUSION

In summary, this meta-analysis finds that IL‑6 rs1800795 and IL‑18 rs1946518 polymorphisms decrease the risk of BD. However, IL‑12B rs3212227 increases BD susceptibility. Further large-scale investigation of this association is necessary.

A protocol of homozygous haploid callus induction from endosperm of Taxus chinensis Rehd. var. mairei

Obtainment and characterization of the novel endosperm callus of Taxus chinensis Rehd. var. mairei are valuable for haploid breeding, genome, and functional genome in Taxus. Callus was obtained by hydropriming with sterile water for 3 days and suitable medium composition. The highest callus induction (70.89 %) and lower browning ratio (7.95 %) were obtained from Gamborg (B5) medium supplemented with 30 g l(-1) of sucrose, 2.5 mg l(-1) of 2,4-dichlorophenoxyacetic (2,4-D), 0.5 mg l(-1) of 6-benzylademine (6-BA) and 7 g l(-1) of agar under dark conditions. The auxin of 2,4-D had a better efficiency of callus induction than naphthylacetic acid, and over 1 mg l(-1) of 6-BA was inhibitory to the callogensis of endosperm. The endosperm callus was haploid which was detectable by the flow cytometry. The genome block of homozygosity of callus was homozygous which was indicated by PCR-based SNP marks. The homozygous haploid of endosperm callus in vitro culture may be useful tools for taxoid-metabolism of gene engineering and bio-fermentation engineering.

Cross-resistance patterns to ACCase-inhibitors in American sloughgrass (Beckmannia syzigachne Steud.) homozygous for specific ACCase mutations

American sloughgrass is a troublesome annual grass weed in winter wheat field rotated with rice in China. The overreliance on acetyl-coenzyme A carboxylase (ACCase) inhibiting herbicides has resulted in resistance evolution in this weed. In this study, the cross-resistance patterns to fenoxaprop-p-ethyl, clodinafop-propargyl, fluazifop-p-butyl, haloxyfop-p-methyl, sethoxydim, clethodim and pinoxaden were established using purified plants individually homozygous for specific mutant ACCase alleles. Results indicated that 1781Leu allele endows high-level resistance to APPs, CHDs and pinoxaden while confers moderate resistance to haloxyfop-p-methyl. The 2027Cys and 2041Asn alleles endow high-level resistance to APPs and pinoxaden and lower level resistance to CHDs. The 2078Gly allele confers high-level resistance to all herbicides tested in this study, however, moderate resistance to sethoxydim. The 2096Ala very likely endows high-level resistance to fluazifop-p-butyl, haloxyfop-p-methyl and moderate resistance to sethoxydim. In addition, one undefined resistance mechanism was involved in population SD-04.

Homozygous delta-beta Thalassemia in a Child: a Rare Cause of Elevated Fetal Hemoglobin

BACKGROUND

Delta beta (δβ) thalassemia is an unusual variant of thalassemia with elevated level of fetal hemoglobin (HbF). Homozygous patients of this disorder, unlike β-thalassemia, show mild anemia. Only few cases of δβ-thalassemia have been reported from India in the available indexed English literature.

CASE PRESENTATION

A four-year old male child was evaluated for recent-onset jaundice. Hematological investigations showed mild anemia with microcytic hypochromic red cells. A comprehensive analysis of hemoglobin by high-performance liquid chromatography (HPLC) showed complete absence of HbA and HbA2 with HbF constituting 100% of the hemoglobin. Hemoglobin analysis of both parents showed elevated level of HbF with normal HbA2. A final diagnosis of δβ-thalassemia in the child with both parents being carriers was rendered.

CONCLUSION

Delta beta-thalassemia is an uncommon cause of markedly elevated fetal hemoglobin beyond fetal period. Clinical and haematological parameters should be evaluated to render an accurate diagnosis.