Cardiac defects were studied in five chromosomally abnormal embryos of 10-14 weeks' gestation by free-hand microdissection of hearts measuring 2.5-6 mm in diameter. The type of cardiac malformation ...alone or in association with other anomalies helped to confirm the chromosome diagnosis established prenatally by chorionic villus sampling or after spontaneous abortion. It was suggestive of a chromosomal disorder in one case in which cytogenetic investigation had failed.
Background: Cytogenetic analysis, Y-chromosome microdeletion
screening, FISH techniques and other genetic methods have helped in
finding the causes of infertility in azoospermic or severe
...oligoazoospermic cases in the last decade. Objective: In the present
study, we characterized an abnormal Y-chromosome, detected as a mosaic
in an azoospermic male ascertained for infertility. Materials and
Methods: Chromosome analysis, using G, Q and C banding techniques and
FISH analyses with several different DNA probes specific for Y and X
chromosome sequences XY centromeric α-satellite, Y
non-α-satellite III, LSI-probes of the Y chromosome, WCP of
Chromosome Y, SRY gene, subtelomeric Xp and Yp, which cover the SHOX
(short stature-homeobox containing) gene, and subtelomeric Xq and Yq
probes were performed. A total of 20 sequence tagged sites were
analyzed using primer sets specific for the Y-chromosome microdeletion
loci. The primers were chosen to cover AZFa, AZFb, and AZFc regions as
well as the SRY gene. Results: Chromosome analysis revealed a
gonosomal mosaicism of monosomy X (51%) and a pseudodicentric Y (49%)
chromosome: mos 45, X/46,X psu dic (Y) (qter→p11.32 ::
p11.2→qter). Molecular genetic studies did not show deletions in
the AZFabc regions, but a deletion was found in the short arms of the
dicentric Y chromosome. One of the SRY genes was also missing.
Conclusion: The azoospermia in this patient could be explained by
either the presence of an abnormal Y-chromosome that cannot form a sex
vesicle (which appears to be necessary for the completion of meiosis
process and the formation of sperm), or the presence of the 45, X cell
line.
