Burmese Head Defect

Brachycephaly, also known as Frontonasal Dysplasia (FND), is a broad group of disorders affecting face and skull development. In the Burmese cat, a form of the disorder known as Burmese Head Defect (BHD) has been observed. The causal mutation for the disease was identified in the Aristaless-Like Homeobox 1 (ALX1) gene. The mutation inherits in a co-dominant manner.

Carriers for the mutation display a milder form of brachycephaly (shortened skull), with short, flat muzzles. As this phenotype has become a distinctive feature of the “contemporary” or American Burmese, the Burmese Head Defect mutation is common among these cats.