Screening for microdeletions of Y chromosome genes in patients undergoing intracytoplasmic sperm injection.
The potential of assisted reproduction techniques to transmit genetic defects causing male infertility raises questions concerning the need for a systematic genetic screen and counselling. Deletions of the long arm of the Y chromosome are frequently associated with a failure of spermatogenesis. The search for Y specific sequences and for the gene families RNA binding motif (RBM) and deleted in azoospermia (DAZ) have been introduced in many laboratories. The incidence of Y microdeletions varies widely between studies, from 1-55%. These differences are mainly related to study design. The highest incidence of microdeletions has been reported in well selected idiopathic azoospermic patients. Since microdeletions have been reported also in non-idiopathic patients, it is important to define what is the deletion frequency in unselected patients. We report Y chromosome microdeletion screening in 134 unselected patients undergoing intracytoplasmic sperm injection (ICSI). In the first part of the study we tested six Y chromosome markers. We found three patients with microdeletions (2.2%). Subdivision of the study population revealed a deletion incidence of 4.7% in azoospermic/cryptozoospermic patients; an incidence of 7% in idiopathic patients and an incidence of 16% in idiopathic azoospermic/cryptozoospermic patients. The second part of the study consisted of a screen for the presence of the Y chromosome genes, DBY, CDY, XKRY, eIF-1A, DAZ and BPY2. No additional gene-specific deletions were found. Further data on gene specific screening are needed especially for selected idiopathic patients.
Krausz
C
C
Andrology Unit, Department of Clinical Physiopathology, Department of Obstetric and Gynecology, University of Florence, Firenze, Italy.
Bussani-Mastellone
C
C
Granchi
S
S
McElreavey
K
K
Scarselli
G
G
Forti
G
G
D001483:Base Sequence; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D003593:Cytoplasm; D017931:DNA Primers / Q000235:genetics; D005260:Female; D005307:Fertilization in Vitro; D005787:Gene Frequency; D005820:Genetic Testing; D006801:Humans; D007248:Infertility, Male / Q000209:etiology / Q000235:genetics* / Q000628:therapy*; D008297:Male; D008845:Microinjections; D009845:Oligospermia / Q000235:genetics / Q000628:therapy; D016133:Polymerase Chain Reaction; D016324:Sequence Tagged Sites; D013094:Spermatozoa; D014998:Y Chromosome / Q000235:genetics*
D017931:DNA Primers