Journal of Genetics最新文献

In the past, there were no easily distinct and recognizable features as a guide for precise clinical and genetic diagnosis of cases with chromosome microdeletions involving 15q26 including CHD2,. The present study analysed the clinical data and collected venous blood samples from a pediatric patient and his healthy family members for DNA testing. The whole-exome sequencing was performed by the next-generation sequencing (NGS). Chromosomal copy-number variations were tested based on NGS. We present a review of all cases with chromosome microdeletions affecting CHD2. A novel de novo 5.82-Mb deletion at 15q25.3-15q26.1 including CHD2 was identified in our patient who is an 11.6-year-old boy. We first found surprising efficacy of lamotrigine in controlling intractable drop seizures in the individual. These cases have development delay, behavioural problems, epilepsy, variable multiple anomalies, etc. Phenotypes of individuals with deletions involving 15q26 including CHD2 are highly variable with regard to facial features and multiple developmental anomalies. We first found the special clinical entity of development delay, behavioural problems, epilepsy, variable skeletal and muscular anomalies, abnormalities of variable multiple systems and characteristic craniofacial phenotypes in patients with chromosome microdeletions involving CHD2. The larger deletions involving 15q26 including CHD2 tend to cause the classical phenotype. A distinctive craniofacial appearance of the classical phenotype is midface hypoplasia and perifacial protrusion.

Vitamin-D deficiency (VDD) is a global health concern. It is known to play a critical role in the immunomodulation, and thus, its metabolism could be investigated to unravel its contribution in common immune-mediated diseases, e.g., celiac disease (CD). Genotyping of SNPs from vitamin D receptor (VDR) gene, such as rs11568820 (Cdx2) and rs2228570 (Fok1) using allele specific multiplex polymerase chain reaction (ASM-PCR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) respectively; and rs7041 and rs4588 of vitamin D binding protein (VDBP/GC) using PCR-RFLP were done in 969 subjects including CD cases (n=506) and controls (n=463). Genotype data for 86 CD and 712 controls for rs11568820 and rs7041 were retrieved from already published Immunochip genotype data. Serum concentration of vitamin-D and vitamin D binding protein (VDBP) were measured for 283 participants (98 CD and 185 controls). rs4588-A allele was identified as protective allele [OR=0.6(0.4-0.7), P<0.0001]. Significantly reduced serum level of vitamin-D was observed in CD patients [median=16.25 ng/mL, IQR (8.94-23.60)] than in controls [median=19.94 ng/mL, IQR (13.91-28.46)] with P=0.001. Notably, rs7041-GG, rs4588-CC, and 1F (GC) haplotype of VDBP/GC showed significant association (P<0.05) with reduced serum vitamin D level. We did not find any significant association with VDBP serum concentration. Significant vitamin D and VDBP level correlations were observed in controls (spearman r = 0.3, P=0.005). The present study highlights the significance of reduced vitamin-D serum level in CD. 1F variant of VDBP. and lower vitamin-D levels contribute to CD. No correlation between vitamin-D and VDBP levels suggests that vitamin-D supplementation may improve vitamin-D levels but might not affect VDBP levels in CD subjects.

Knowledge of genetic variability within and among types and breeds of dromedary (Camelus dromedarius L.) can be a valuable asset in selective breeding of desirable characteristics and will shed light on their origin, dynamics of domestication, and dispersion. Variability in an 809 bp segment of the mtDNA genome was measured within and among dromedaries from eight indigenous and one exogenous breed from Ha'il in north-central Saudi Arabia. Sixteen mtDNA haplotypes were identified among 47 camels. Haplotypic diversity among breeds is high (H_d = 0.817); most of the AMOVA variance (55.05%) occurs within breeds. Phylogenetic comparison of these haplotypes with those obtained across their geographic range showed that most haplotypes were placed within the same cluster with ancient wild dromedaries and the two newly identified haplotypes in this study. The most prevalent haplotypes found in dromedaries from this area appear to be ancestral to most other dromedaries and differ from each other by only one SNP. These results support the hypothesis that the Arabian Peninsula is a hub of diversification for dromedaries.

The mitogenome is an important tool for taxonomic and evolutionary investigation. Here, a few complete mitogenomes of red algae have been reported. We have reported the complete mitogenome sequences of Grateloupia cornea Okamura, 1913 (Rhodophyta, Halymeniales). The genome is 30,595 bp in circumference, and has a strongly biased [AT] = 66.9%. Like most other Grateloupia species, it has a group II intron in the cox1 gene. Maximum likelihood and maximum parsimony analyses showed that G. cornea is more closely related to G. asiatica. This shows that the group II intron in the cox1 ORF present in most species of Grateloupia was present in their common ancestor, and uniquely lost in G. asiatica. The seven Grateloupia species with known mitogenome sequences remain monophyletic, with the genus Polyopes as sister taxon. The complete mitochondrial genome data will be valuable for future research on comparative mitochondrial genome analysis, an extensive understanding of gene content and organization, evolution of the cox1 intron in Rhodophyta as well as phylogenetic analysis.

Cancer is a multifactorial, multi-step process of pathogenesis; however, in the case of familial cancers, genetic aetiology can play a significant role. Identifying genetic variants in cancer patients having a strong family history of cancer as well as their unaffected blood relatives can unravel their role in predisposition to cancer. Here, we report the findings of whole-exome sequencing in a patient (77/F) diagnosed with ovarian cancer and her daughters (61/F) and (59/F) who were diagnosed with breast and ovarian cancers along with her asymptomatic son (53/M). All the four family members show segregation of RAD51D (rs200564819). Other incidental findings ADAMTS13 (rs142572218) and SYCE1 (rs201873178) genetic variants in proband and son, and LIAS (rs546751789) and PDHA1(rs747051654) genetic variants in son have also been reported.

Dissecting the molecular basis of adaptation remains elusive despite our ability to sequence genomes and transcriptomes. At present, most genomic research on selection focusses on signatures of selective sweeps in patterns of heterozygosity. Other research has studied changes in patterns of gene expression in evolving populations but has not usually identified the genetic changes causing these shifts in expression. Here we attempt to go beyond these approaches by using machine learning tools to explore interactions between the genome, transcriptome, and life-history phenotypes in two groups of 10 experimentally evolved Drosophila populations subjected to selection for opposing life history patterns. Our findings indicate that genomic and transcriptomic data have comparable power for predicting phenotypic characters. Looking at the relationships between the genome and the transcriptome, we find that the expression of individual transcripts is influenced by many sites across the genome that are differentiated between the two types of populations. We find that single-nucleotide polymorphisms (SNPs), transposable elements, and indels are powerful predictors of gene expression. Collectively, our results suggest that the genomic architecture of adaptation is highly polygenic with extensive pleiotropy.

Trachoma, caused by Chlamydia trachomatis, is the most common infectious blindness in the world and is present in indigenous Mayan from Chiapas (Mexico). Inflammatory genes are activated when suffering from trachoma, thus some polymorphisms could increase the susceptibility to develop irreversible blindness. This study aimed to evaluate the genetic risk of developing late-stage trachoma in Mayan ethnic groups. In a case-control study (n = 51 vs n = 102, respectively), the following single-nucleotide polymorphisms (SNPs) in genes related to inflammation were analysed: HSD11B1 (rs11807619), HSD11B1 (rs932335), ABCG2 (rs2231142), SLCO1B1 (rs4149056), IL-10 (rs1800890), TNF (rs1800629), MMP2 (rs243865) and ACE. Three SNPs were associated with late-stage trachoma risk: (i) the T allele of rs11807619, (ii) the C allele of rs932335, which are linked to the HSD11B1 gene (OR = 22.5-27.3), particularly in men when adjusts for gender (OR = 16-16.7); and (iii) D allele of rs4340 in the ACE gene (OR = 5.2-5.3). In fact, significant linkage disequilibrium demonstrated association between ACE gene and HSD11B1 SNPs (r = 0.17-0.179; P = 0.0048-0.0073). Two SNPs HSD11B1 gene (P = 0.013 vs 0.0039) and HSD11B1-ACE haplotypes showed association with late-stage trachoma in Mayan ethnic groups.

Typhoid is endemic in India and has high global incidence. There were large outbreaks of typhoid in India between 1990 and 2018. Available typhoid vaccines induce variable levels of protective antibodies among recipients; thus, there is variability in response to the vaccine. Interindividual genomic differences is hypothesized to be a determinant of the variability in response. We studied the antibody response of ~1000 recipients of the Vi-polysaccharide typhoid vaccine from Kolkata, India, who showed considerable variability of antibody response, i.e., anti-Vi-polysaccharide antibody level 28 days postvaccination relative to prevaccination. For each vaccinee, wholegenome genotyping was performed using the Infinium Global Screening Array (Illumina). We identified 39 SNPs that mapped to 13 chromosomal regions to be associated with antibody response to the vaccine; these included SNPs on genes LRRC28 (15q26.3), RGS7 (1q43), PTPRD (9p23), CERKL (2q31.3), DGKB (7p21.2), and TCF4 (18q21.2). Many of these loci are known to be associated with various blood cell traits, autoimmune traits and responses to other vaccines; these genes are involved in immune related functions, including TLR response, JAK-STAT signalling, phagocytosis and immune homeostasis.

Intellectual developmental disorder, X-linked 104 (XLID104), caused by the FRMPD4 gene variant, is a rare X-linked genetic disease that primarily manifests as intellectual disability (ID) and language delay, and may be accompanied by behavioural abnormalities. Currently, only 11 patients from four families have been reported to carry FRMPD4 gene variants. Here, we report a rare case of a Chinese patient with XLID104 who was presented with severe ID and language impairment. Genetic testing results showed that the patient had a novel hemizygous variant on FRMPD4 inherited from the heterozygous variant NM_001368397: c.1772A>C (p.Glu591Ala) carried by his mother. To our knowledge, this variant has not been reported previously. Western blot results for the recombinant plasmid constructed in vitro indicated that the expression of the mutant protein may be reduced. Using molecular dynamics simulations, we predicted that the mutant protein may affect the interaction of the FRMPD4 protein with DLG4. In this study, we expand the spectrum of FRMPD4 variants and suggest that the clinical awareness of the genetic diagnosis of nonsyndromic ID should be strengthened.

Kruppel-like factor 1 (KLF1) is an essential erythroid-specific transcription factor. Several reports have shown that KLF1 gene mutations are associated with increased levels of Hb F and Hb A₂. However, scarce population studies have analysed common KLF1 variations. This study examines the potential association with Hb F and Hb A₂ levels in β-thalassemia (β-thal) carriers of Portugueseancestry of the four common KLF1 gene variants: -251C>G (rs3817621) and -148G>A (rs79334031), in the promoter region; and c.115A>C (p.Met39Leu) (rs112631212) and c.304T>C (p.Ser102Pro) (rs2072597), in exon 2. Ninety-two Portuguese β-thal carriers (43 males and 49 females) aged 2 to 77 years old (mean 32.55 years) were engaged in the study. Hb F levels range from 0.2 to 12.5% and Hb A₂ was above the normal level, ranging from 3.6 to 6%. The Hb A₂ and Hb F levels were determined by high-performance liquid chromatography. Single-nucleotide polymorphisms were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Minor allele frequencies for SNPs rs3817621 (G), rs79334031 (A), rs112631212 (C) and rs2072597 (C) were 0.196, 0.016, 0.011 and 0.169, respectively. Basic simple linear regression in the total population showed no significant associations with the levels of Hb F (P>0.05). For the low-frequency variant -148A, a statistically significant association was found with increased levels of Hb A₂ (β = 0.855; P = 0.017). In conclusion, an association signal with Hb A₂ levels was observed for the variant -148A>G (rs79334031). The complex pattern of SNP interactions related to their influence on the KLF1 transcriptional activity mayexplain the absence of association with Hb F levels.