sheep breed. In a preliminary study, Finocchiaro et al.
(2000) reported the genetic control of the disorder as a
Mendelian recessive trait and without concomitant chromosomal
rearrangements. Subsequently, Finocchiaro et al.
(2003a) sequenced the hr gene (GenBank Acc. No.
AY130969) in the Valle del Belice sheep breed and have
reported that a single nucleotide polymorphism (SNP), in
particular a C-T transition at position 1312 bp in exon 3,
caused an amino acid change at position 438 (Gln/Stop) of
the mature protein. The T nucleotide, resulting in the TAG
stop codon and in homozygote condition, has been associated
with hypotrichotic phenotype in Valle del Belice
sheep breed. Recently, the ovine hr gene has been physically
mapped on chromosome 2 using fluorescence in situ
hybridization (FISH) by Finocchiaro et al. (2008).