The Principles of Clinical Cytogenetics - Extra Materials - Springer

262 Linda Marie Randolph
chromosome. Chromosome aneuploidy rates for chromosomes 18, X and Y determined by FISH (see
Chapter 17) were high in the ICSI candidates with and without constitutional chromosome abnormalities,
both for the sex chromosomes and chromosome 18, compared to the normal controls. The
authors concluded that males with sex chromosome abnormalities have no higher risk of producing
offspring with a sex chromosome abnormality by ICSI than do OAT males with normal karyotypes.
Viville et al. (43) examined the role of morphology of spermatozoa and chromosome abnormalities
of the spermatozoan. They examined specimens from a patient with shortened flagella syndrome,
a patient with globozoospermia, a patient with spermatozoa with irregular acrosomes, and a patient
with macrocephalic spermatozoa with associated multiple flagella. From 1656 to 5000 spermatozoa
were analyzed from patients and from 5064 to 7423 spermatozoa from controls. They employed
three-color FISH and found that patients 1–3 had signals that compared with normal controls. Patient 4,
the one with macrocephalic spermatozoa, showed an elevated Y-to-X ratio and elevated aneuploidy to
diploidy rate. The authors therefore concluded that patients with the first three forms of teratozoospermia
are good candidates for ICSI, and patients with macrocephalic spermatozoa are not.
However, in his review of genetic risks of ICSI, Johnson (23) cited a publication that suggested
spermatozoa with amorphous, round and elongated heads are associated with an increased frequency
(26%) of structural chromosome abnormalities, when compared with that of morphologically normal
spermatozoa.
Bonduelle et al. (44) performed a study to determine whether prenatal cytogenetic abnormalities
after ICSI could be related to sperm parameters. Of 1586 fetuses, chorionic villus sampling (CVS)
(see Chapter 12) was performed on 698, and amniocentesis was performed on 888. Of these, 47 (3%)
had abnormal karyotypes, and 25 of the 47, or 2%, were de novo. They found a 2.1% de novo prenatal
chromosome abnormality rate for sperm concentrations of < 20 × 10 6/ mL and a 0.24% abnormality
rate for sperm concentrations of 20 × 10 6 /mL or greater. The likelihood of a chromosome abnormality
was associated with spermatozoa motility and concentrations, but not morphology in this study. A
de novo chromosome abnormality rate of 1.6% (vs 0.5% risk for women aged 33.5 years (p