Brachydactyly type D

Brachydactyly type D is a genetic trait in which the thumb is relatively short and round, with a wider nail bed. It is also called murderer's thumb, stubbed thumb, spoon thumb, power thumb, short thumb or toe thumb. The distal phalanx of an affected thumb is about two thirds the length of that of a full-length thumb. It is the most common form of shortness of the digits, known as brachydactyly, and is estimated to affect about 2 percent of the population. The trait is associated with the HOXD13 gene, located on chromosome 2q31.1. It is generally regarded as a harmless variation of hand form and is best understood as an inherited feature rather than an illness.