aCGH assay in a Chinese family with syndactyly type 1-c. Homo sapiens

Syndactyly type 1 (SD1) is an autosomal dominant limb malformation characterized in its classical form by complete or partial webbing between the third and fourth fingers and/or the second and third toes. Four subtypes (a, b, c and d) are defined based on variable phenotypes, but the disease genes remain unidentified. SD1-a have been mapped to chromosome 3p21.31 and SD1-b to 2q34-q36. SD1-c and SD1-d are very rare and no gene loci are known for them. We performed linkage and haplotype analyses in two Han Chinese families with SD1-c, and refined the disease locus to 2q31- 2q32. In the large family A, mutation of c.917G>A (p.R306Q) in the homodomain of HOXD13 was indentified. Family B was confirmed with genetic homogeneity and the mutation was c.916C>G (p.R306G). CNV analysis by array CGH excluded possible microdeletion or microduplication. Overall design: SD1c patient sample in the SD1c family vs common control outside the family, healthy control sample in the SD1c family vs common control outside the family