The Principles of Clinical Cytogenetics - Extra Materials - Springer

260 Linda Marie Randolph
Table 8
Constitutional Chromosome Abnormalities in Men with Azoospermia
Compared with Chromosome Abnormalities in Pooled Newborn Series
47,XXY/ Other sex Y chrom Rob Recip
47,XXY 46,XY chrom num struct 46,XX trans trans Inv Mar
N (%) (%) abn (%) abn (%) (%) (%) (%) (%) (%)
383 49 1 1 3 1 4
106 7 4 2 4 2
68 12 1 1 2 1 1
36 1 1 1 1 1
33 6 1
53 13 1 2 1 1
163 31 7 1 1 1
8 4 31
20 3 1 1
356 21 4 2 1 2
34 1 1
53 9
54 2 1 2
Total 159 13 12 15 11 (0.76) 2 (0.14) 11 (0.76) 1 (0.07) 1 (0.07)
1,450 (11.0%)
Newborns 39/36,855 — — a — 51/59,514 55/59,514 7/59,514 13/59,514
(0.11) (0.09) (0.09) (0.01) (0.02)
Abbreviations: N = number of men studied in that series; Other sex chrom num abn = other sex chromosome numerical
abnormalities; Y chrom struct abn = Y chromosome structural abnormalities; Rob trans = Robertsonian translocation;
Recip trans = reciprocal translocation; Inv = inversion; Mar = marker chromosome.
a Source: Ref. 26.
Table 9
AZF Gene Regions and their Usual Phenotypes
Gene region Phenotype
AZFa Absence of germ cells, aka Sertoli cell-only syndrome (SCOS)
AZFb Maturation arrest at spermatocyte stage
AZFc Variable from SCOS to severe oligospermia
AZFd Mild oligospermia or normal cell counts with abnormal sperm morphology
Source: Ref. 29.
to the site of obstruction or from the testis, or it could be taken from several collections of semen that
have been ultracentrifuged to collect any spermatozoa that might be present. Using micromanipulation
techniques, an embryologist grasps the ovum with one instrument and a spermatozoan with
another and injects the spermatozoan into the cytoplasm of the ovum. This has been used for several
years for 47,XXY men and for men with severe male factor infertility for other reasons.
Although this technique has allowed for people to have biological children who would not otherwise
have been able to, serious consideration of transmissible genetic conditions to offspring must be
given and genetic counseling should be offered to couples prior to undergoing the procedure (see
Chapter 20).