Sub-Exome Target Sequencing in a Family With Syndactyly Type IV Due to a Novel Partial Duplication of the LMBR1 Gene: First Case Report in Fujian Province of China

• Published in: Frontiers in genetics Vol. 11; p. 130
• Main Authors: Shi, Lijing, Huang, Hui, Jiang, Qiuxia, Huang, Rongsen, Fu, Wanyu, Mao, Liangwei, Wei, Xiaoming, Cui, Huanhuan, Lin, Keke, Cai, Licheng, Yang, You, Wang, Yuanbai, Wu, Jing
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 28.02.2020
• Subjects: Genetics; LMBR1; sub-exome target sequencing; syndactyly type IV; tibial and fibulal shortening; triphalangeal thumb-polysyndactyly syndrome; tibial and fibulal shortening; LMBR1; syndactyly type IV; sub-exome target sequencing; triphalangeal thumb-polysyndactyly syndrome
• ISSN: 1664-8021; 1664-8021
• DOI: 10.3389/fgene.2020.00130

Syndactyly is one of the most frequent hereditary limb malformations with clinical and genetical complexity. Autosomal dominant syndactyly type IV (SD4) is a rare form of syndactyly, caused by heterozygous mutations in a sonic hedgehog ( ) regulatory element ( ) which resides in intron 5 of the gene on chromosome 7q36.3. SD4 is characterized by complete cutaneous syndactyly of the fingers, accompanied by cup-shaped hands due to flexion of the fingers and polydactyly. Here, for the first time, we reported a large Chinese family from Fujian province, manifesting cup-shaped hands consistent with SD4 and intrafamilial heterogeneity in clinical phenotype of tibial and fibulal shortening, triphalangeal thumb-polysyndactyly syndrome (TPTPS). We identified a novel duplication of ∼222 kb covering exons 2-17 of the gene in this family by sub-exome target sequencing. This case expands our new clinical understanding of SD4 phenotype and again confirms the feasibility to detect copy number variation by sub-exome target sequencing.