Letter to the Editor Diagnostic Genetics Identification of p.Glu131Lys Mutation in the IHH Gene in a Korean Patient With Brachydactyly Type A1

Brachydactyly is a heterogeneous group of inherited disorders of the digits, characterized by shortened fingers and/or toes [1]. Brachydactyly can occur as an isolated feature or as a part of a complex malformation syndrome [2]. Isolated brachydactylies have been classified into five types, A through E, on the basis of digit malformation. Among them, brachydactyly type A1 (BDA1; MIM 112500) is characterized by bilaterally symmetrical short-ening or absence of the middle phalanges of most digits [1]. BDA1 is a rare hand malformation with few reported pedi-grees. The phenotypic variability of BDA1 has been docu-mented in familial cases and includes additional features such as other hand/foot malformations, scoliosis, and short stature [1]. Genes associated with BDA1 include IHH [3], BDA1B [4], and GDF5 [5]. To our knowledge, no BDA1 case has been con-firmed by molecular genetic analysis in the Korean population