Frontiers in Genetics (Feb 2020)

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

  • Lijing Shi,
  • Hui Huang,
  • Qiuxia Jiang,
  • Rongsen Huang,
  • Wanyu Fu,
  • Liangwei Mao,
  • Liangwei Mao,
  • Xiaoming Wei,
  • Huanhuan Cui,
  • Keke Lin,
  • Licheng Cai,
  • You Yang,
  • Yuanbai Wang,
  • Jing Wu

DOI
https://doi.org/10.3389/fgene.2020.00130
Journal volume & issue
Vol. 11

Abstract

Read online

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 (SHH) regulatory element (ZRS) which resides in intron 5 of the LMBR1 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 LMBR1 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.

Keywords