A familial case of Syndactyly type IV due to a novel duplication of ~222.23 kb covering exons 2-17 of the LMBR1 gene: a case report

Shi, L.; Huang, H.; Jiang, Q.; Huang, R.; Fu, W.; Mao, L.; Wei, X.; Cui, H.; Lin, K.; Cai, L.; Yang, Y.; Wang, Y.; Wu, J.

doi:10.1101/420588

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bioRxiv · 10.1101/420588

A familial case of Syndactyly type IV due to a novel duplication of ~222.23 kb covering exons 2-17 of the LMBR1 gene: a case report

Shi, L.·Huang, H.·Jiang, Q.·Huang, R.·Fu, W.·Mao, L.·Wei, X.·Cui, H.·Lin, K.·Cai, L.·Yang, Y.·Wang, Y.·Wu, J.

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Abstract

Syndactyly is one of the most frequent hereditary limb malformations with clinical and genetical complexity. Autosomal dominant Syndactyly type IV (SD4) is a very rare form of syndactyly, occurring as a result of heterozygous mutation in an SHH regulatory element (ZRS) that resides in intron 5 of the LMBR1 gene on chromosome 7q36.3. The SD4 is characterized by complete cutaneous syndactyly of all fingers, cup-shaped hands due to flexion of the fingers and accompanied by polydactyly. Here, we firstly reported a big Chinese family, manifesting cup-shaped hands consistent with SD4 and intrafamilial heterogeneity in clinical phenotype of tibial and fibulal shortening, triphalangeal thumb-polysyndactyly syndrome (TPTPS). Genetically, we identified a novel duplication of [~]222.23 kb covering exons 2-17 of the LMBR1 gene in this family by next generation sequencing. This case expands our new clinical understanding of SD4 phenotype.

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Shi, L., Huang, H., Jiang, Q., Huang, R., Fu, W., Mao, L., Wei, X., Cui, H., Lin, K., Cai, L., Yang, Y., Wang, Y., Wu, J.. 2018-09-18. A familial case of Syndactyly type IV due to a novel duplication of ~222.23 kb covering exons 2-17 of the LMBR1 gene: a case report. https://doi.org/10.1101/420588

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