scholarly journals A novel variant of IHH in a Chinese family with brachydactyly type 1

2020 ◽  
Author(s):  
Qi Yang ◽  
Jin Wang ◽  
Xiaoxian Tian ◽  
Fei Chen ◽  
Jing Lan ◽  
...  

Abstract Brachydactyly type A1(BDA-1) is an autosomal dominant disorder which is caused by heterozygous pathogenic variants in a specific region of the N-terminal active fragment of Indian Hedgehog ( IHH ). The disorder is mainly characterized by shortening or missing of the middle phalanges. The following study revealed a novel heterozygous missense variant c.299A>G (p.D100G) at the mutational hotspot of IHH gene after performing whole-exome sequencing in the proband of a Chinese family with BDA-1. The variant co-segregated with BDA-1 in the pedigree, showed 100% penetrance for phalange phenotype with variable expressivity. This finding expanded the variants on IHH gene which contribute to the cause of BDA-1.

2019 ◽  
Author(s):  
Qi Yang ◽  
Jin Wang ◽  
Xiaoxian Tian ◽  
Fei Chen ◽  
Jing Lan ◽  
...  

Abstract Brachydactyly type A1(BDA-1) is an autosomal dominant disorder which is caused by heterozygous pathogenic variants in a specific region of the N-terminal active fragment of Indian Hedgehog ( IHH ). The disorder is mainly characterized by shortening or missing of the middle phalanges. The following study revealed a novel heterozygous missense variant c.299A>G (p.D100G) at the mutational hotspot of IHH gene after performing whole-exome sequencing in the proband of a Chinese family with BDA-1. The variant co-segregated with BDA-1 in the pedigree, showed 100% penetrance for phalange phenotype with variable expressivity. This finding expanded the variants on IHH gene which contribute to the cause of BDA-1.


2019 ◽  
Author(s):  
Qi Yang ◽  
Jin Wang ◽  
Xiaoxian Tian ◽  
Fei Chen ◽  
Jing Lan ◽  
...  

Abstract Brachydactyly type A1 (BDA-1, MIM 112500) is a genetically heterogeneous autosomal-dominant disorder mainly characterized by shortening or missing of the middle phalanges. Brachydactyly type A1 (BDA-1) is caused by heterozygous pathogenic variants in a specific region of the N-terminal active fragment of Indian Hedgehog (IHH). In this study, we reported a Chinese family with 8 members affected with Brachydactyly type A1. After performing whole-exome sequencing in the proband, we identified a novel heterozygous missense variant c.299A>G (p.D100G) at the mutational hotspot of IHH gene. The variant co-segregated with BDA-1 in the pedigree, showed 100% penetrance for phalange phenotype with variable expressivity. This finding expanded the Brachydactyly type A1-related mutational spectrum of IHH gene.


2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Jian-Xia Tang ◽  
Xiang-Shui Xiao ◽  
Kai Wang ◽  
Jie-Yuan Jin ◽  
Liang-Liang Fan ◽  
...  

Background. Cleft lip with or without cleft palate (CL/P) is the most common facial birth defect, with a worldwide incidence of 1 in 700-1000 live births. CL/P can be divided into syndromic CL/P (SCL/P) and nonsyndromic CL/P (NSCL/P). Genetic factors are an important component to the etiology of NSCL/P. ARHGAP29, one of the NSCL/P disease-causing genes, mediates the cyclical regulation of small GTP binding proteins such as RhoA and plays an essential role in cellular shape, proliferation, and craniofacial development. Methods. The present study investigated a Chinese family with NSCL/P and explored potential pathogenic variants using whole-exome sequencing (WES). Variants were screened and filtered through bioinformatic analysis and prediction of variant pathogenicity. Cosegregation was subsequently conducted. Results. We identified a novel heterozygous missense variant of ARHGAP29 (c.2615C > T, p.A872V) in a Chinese pedigree with NSCL/P. Conclusion. We detected the disease-causing variant in this NSCL/P family. Our identification expands the genetic spectrum of ARHGAP29 and contributes to novel approaches to the genetic diagnosis and counseling of CL/P families.


2020 ◽  
Vol 2020 ◽  
pp. 1-5
Author(s):  
Hao Geng ◽  
Dongdong Tang ◽  
Chuan Xu ◽  
Xiaojin He ◽  
Zhiguo Zhang

Background. Split-hand/foot malformation (SHFM) is a severe congenital disability mainly characterized by the absence or hypoplasia of the central ray of the hand/foot. To date, several candidate genes associated with SHFM have been identified, including TP63, DLX5, DLX6, FGFR1, and WNT10B. Herein, we report a novel variant of TP63 heterozygously present in affected members of a family with SHFM. Methods. This study investigated a Chinese family, in which the proband and his son suffered from SHFM. The peripheral blood sample of the proband was used to perform whole-exome sequencing (WES) to explore the possible genetic causes of this disease. Postsequencing bioinformatic analyses and Sanger sequencing were conducted to verify the identified variants and parental origins on all family members in the pedigree. Results. By postsequencing bioinformatic analyses and Sanger sequencing, we identified a novel missense variant (NM_003722.4:c.948G>A; p.Met316Ile) of TP63 in this family that results in a substitution of methionine with isoleucine, which is probably associated with the occurrence of SHFM. Conclusion. A novel missense variant (NM_003722.4:c.948G>A; p.Met316Ile) of TP63 in SHFM was thus identified, which may enlarge the spectrum of known TP63 variants and also provide new approaches for genetic counselling of families with SHFM.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Yu Sui ◽  
Yongping Lu ◽  
Meina Lin ◽  
Xiang Ni ◽  
Xinren Chen ◽  
...  

Abstract Background Milroy disease (MD) is a rare, autosomal-dominant disorder. Variants in the Fms-related tyrosine kinase 4 (FLT4/VEGFR3) gene cause the symptoms of this disease. In this report, we investigated the variant in a large Chinese family with MD. Methods We conducted Sanger sequencing of exons 17–26 of FLT4/VEGFR3 (NM_182925.4). We assessed its pathogenicity based on the ACMG criteria and predicted it with an in silico program. Results A heterozygous substitution (NM_182925.4 (FLT4/VEGFR3):c.2774 T>A, p. (Val925Glu)) was detected in all patients with MD but not in any healthy controls. The variant was evaluated as pathogenic according to the ACMG criteria and was predicted to be pathogenic using an in silico program. Conclusions In this report, we described a large family with MD caused by a missense variant in FLT4/VEGFR3 (NM_182925.4 (FLT4/VEGFR3_v001):c.2774 T>A, p. (Val925Glu)). There are phenotypic heterogeneities among family members, and further research should be conducted to explore the possible reasons.


Author(s):  
Zhifan Zhou ◽  
Yong Zeng ◽  
Xinchun Wu ◽  
Fei Li ◽  
Xiaoyan Liu ◽  
...  

Neurofibromatosis type1 (NF1) is an autosomal dominant disorder caused by mutations in the NF1gene. Although congenital pseudarthrosis of the tibia (CPT) has frequently been associated with NF1, the underlying molecular mechanism of CPT in these NF1 patients is yet ill-understood. The aim of the present study was to detect NF1 mutations from genomic DNA and to harbor variants associated with CPT in NF1 patients. Whole-exome sequencing was first carried out with samples from two patients with CPT in one NF1 family, and a novel mutation c.2324A>G (p.E775G) in NF1 gene was identified. Additionally, a missense variant c.455C>T (p.P152L) in BCOR gene completely co-segregated with the CPT phenotype within this family. Subsequently, NF1 and NF2 genes in four other unrelated patients with both NF1 and CPT were screened using targeted sequencing. Four mutations in NF1 gene, including two known mutations (c.2288T>C/p.L763P, c.574 C>T/p.R192*) and two novel mutations (c.768delT/p.F256Lfs*25, c.2229_2230delTG/ p.V744Qfs*23) were detected. Further study confirmed that CPT was present in NF1 families, and NF1 mutations were closely associated with these complex phenotypes. Moreover, the data from the current study indicated that male gender might be a susceptibility factor for CPT in NF1. Therefore, we speculated that BCOR variants might be related to CPT phenotype among male NF1 patients.


2018 ◽  
Vol 6 ◽  
pp. 2050313X1881871 ◽  
Author(s):  
Rosettia Ho ◽  
Adam D McIntyre ◽  
Brooke A Kennedy ◽  
Robert A Hegele

Isolated brachydactyly is an umbrella term describing disproportionally shortened fingers and toes, often following an autosomal dominant mode of inheritance. Various forms of brachydactyly have been characterized and several causative genes have been found, but many types remain genetically undefined. We describe an Ontario family with mild brachydactyly in which whole-exome sequencing identified a novel variant for brachydactyly type A1 (exon 1, c.285_287dupGAA, p.Glu95_Asn96insLys) in the Indian hedgehog ( IHH) gene. This rare variant co-segregated with affected status in the pedigree and was associated with (1) shortened middle phalange length by 21.1% ( p < 0.001); (2) shortened palm length by 13.8% ( p < 0.01); (3) reduced digit-palm ratio by 6.8% ( p < 0.03); and (4) reduced stature by 9.5% ( p < 0.001). We report the first IHH in-frame insertion causing brachydactyly type A1.


2019 ◽  
Vol 32 (12) ◽  
pp. 1385-1389
Author(s):  
Aman Ullah ◽  
Ranjha Khan ◽  
Muhammad Naeem

Abstract Background Familial hypokalemic periodi9c paralysis (hypoKPP) is a rare autosomal dominant disorder characterized by episodic paralytic attacks caused by fall in blood potassium. CACNA1S, SCN4A or KCNJ2 variants can cause hypoKPP. Case presentation We investigated a Pakistani family affected with autosomal dominant familial hypoKPP through whole exome sequencing (WES). A heterozygous KCNJ2 missense variant c.919A > G was found segregating with the disease phenotype in the family. Conclusions The KCNJ2 missense variant is the likely cause of the disorder in the affected family. The finding should help improve antenatal screening and genetic counselling of this family.


2022 ◽  
Vol 12 ◽  
Author(s):  
Fengyu Che ◽  
Jiangang Zhao ◽  
Yujuan Zhao ◽  
Zhi Wang ◽  
Liyu Zhang ◽  
...  

Aim: To determine the etiology of a Chinese family with thrombocytopenia by analyzing the clinical features and genetic variation.Methods: Clinical profiles and genomic DNA extracts of the family members were collected for the study. Whole exome sequencing and Sanger sequencing was used to detect the associated genetic variation and verify the family co-segregation respectively. Bioinformatics analysis assessed the pathogenicity of missense mutations.Results: The study reported a 3-generation pedigree including eight family members with thrombocytopenia. The platelet counts of the patients were varied, ranging from 38 to 110 × 109/L (reference range: 150–450 x 109/L). The mean volumes and morphology of the sampled platelet were both normal. The bleeding abnormality and mitochondriopathy were not observed in all the patients. Clinical signs of thrombocytopenia were mild. A novel heterozygous missense variant c.79C &gt; T (p.His27Tyr) was identified in CYCS gene associated with autosomal dominant thrombocytopenia.Conclusion: We report the first large family with autosomal dominant non-syndromic thrombocytopenia 4 in a Chinese family, a novel heterozygous missense variant c.79C &gt; T (p.His27Tyr) was identified. The whole exome sequencing is an efficient tool for screening the variants specifically associated with the disease. The finding enriches the mutation spectrum of CYCS gene and laid a foundation for future studies on the correlation between genotype and phenotype.


Author(s):  
Qing Li ◽  
Chengfeng Wang ◽  
Wei Li ◽  
Zaiqiang Zhang ◽  
Shanshan Wang ◽  
...  

AbstractPontine autosomal dominant microangiopathy and leukoencephalopathy (PADMAL) is a rare hereditary cerebral small vessel disease. We report a novel collagen type IV alpha 1 (COL4A1) gene mutation in a Chinese family with PADMAL. The index case was followed up for 6 years. Neuroimaging, whole-exome sequencing, skin biopsy, and pedigree analysis were performed. She initially presented with minor head injury at age 38. MRI brain showed chronic lacunar infarcts in the pons, left thalamus, and right centrum semiovale. Extensive workup was unremarkable except for a patent foramen ovale (PFO). Despite anticoagulation, PFO closure, and antiplatelet therapy, the patient had recurrent lacunar infarcts in the pons and deep white matter, as well as subcortical microhemorrhages. Whole-exome sequencing demonstrated a novel c.*34G > T mutation in the 3′ untranslated region of COL4A1 gene. Skin biopsy subsequently demonstrated thickening of vascular basement membrane, proliferation of endothelial cells, and stenosis of vascular lumen. Three additional family members had gene testing and 2 of them were found to have the same heterozygous mutation. Of the 18 individuals in the pedigree of 3 generations, 12 had clinical and MRI evidence of PADMAL. The mechanisms of both ischemic and hemorrhagic stroke are likely the overexpression of COLT4A1 in the basement membrane and frugality of the vessel walls. Our findings suggest that the novel c.*34G > T mutation appears to have the same functional consequences as the previously reported COL4A1 gene mutations in patients with PADMAL and multi-infarct dementia of Swedish type.


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