Lack of the T54A polymorphism of the DAZL gene in infertile Italian patients.

The Thr54Ala polymorphism of the deleted-in-azoospermia-like (DAZL) protein has been associated with susceptibility to spermatogenic failure in the Taiwanese population. We used single-strand conformation polymorphism and restriction fragment analyses to investigate the presence of the A-->G transition in exon 3 of the DAZL gene in 95 infertile Italian patients. The patients had oligozoospermia or non-obstructive azoospermia with different degrees of testicular cytological picture. The allele carrying T54A polymorphism was not present in this group of patients nor in 63 controls, indicating that the frequency of this putative mutation is <1% in Italy. Since the Italian population usually shows allelic frequencies similar to the other Caucasian populations, we suggest that the T54A allele might play a role in infertility only in Taiwanese or Asiatic individuals.