F24 CONGENITAL ATRICHIA IN A PALESTINIAN FATIENT RESULTING FROM A MUTATION IN THE HUMAN HAIRLESS GENE

¹Zlotogorski A., ²Christiano A.M. ¹Dept. of Dermatology, Hadassah Medical Center, Jerusalem, Israel; ²Department of Dermatology and Genetics & Development, Columbia University, New York, USA.

Congenital atrichia with papular lesions is a rare, recessively inherited disorder characterized by a complete absence of hair and hair follicles, as well as papular, cystic skin lesions.  We and others recently reported several pathogenic missense, nonsense and deletion mutations in the human hairless gene (8p12) in this form of atrichia in families from around the world.  

We studied a Palestinian family with a single member affected with congenital atrichia. The proband, a 5-year-old-girl was born with normal hair, which began to shed at the age of three months and progressed to complete hairlessness at the age of nine months.   Hair was absent from the scalp and eyebrows and eyelashes were sparse. She had the additional characteristics features of grouped cystic and papular lesions distributed mainly on the cheeks, arms and thighs.  We identified a homozygous G-to-A transition at amino acid 1056 in the hairless gene leading to the conversion of a valine residue (GTG) to a methionine residue (ATG).  This mutation, abolishes a restriction endonuclease site for the enzyme Pml 1, which was used as a screening assay in 40 Caucasian control individuals, and 98 Palestinian control individuals, to rule out the possibility that this mutation is a polymorphism.  The absence of this mutation in 276 alleles supports that it is in fact the pathogenetic mutation in this family.  The clinical findings in this patient with the newly identified mutation are identical to the previously described patients around the world.