The chance of a male with severe oligozoospermia or azoospermia achieving a pregnancy has undergone a revolutionary increase with the introduction of the intracytoplasmic sperm injection technique (ICSI). However, since ICSI circumvents part of the natural sperm selection mechanisms, the possible transmission of genetic defects to the offspring is a major concern. Cytogenetic analysis is a relatively simple technique to identify at least the carriers of a chromosomal aberration before starting the ICSI procedure. In order to assess the frequency of chromosomal aberrations in male ICSI candidates, we have performed a nationwide cytogenetic study. Of the 1792 males examined, 72 (4.0%) revealed a chromosomal aberration, and one individual even had two. Numerical sex chromosomal aberrations and Robertsonian translocations predominated, followed by reciprocal translocations, inversions and supernumerary marker chromosomes. The different implications, in case a chromosomal aberration is encountered prior to ICSI, are discussed.

Chromosomal rearrangements involving 3q26 either due to inversion or translocation with various partner chromosomes are a recurrent finding in malignant myeloid disorders. Typically, these chromosome aberrations contribute to ectopic expression of or to the formation of fusion genes involving the EVI1 proto-oncogene. Chromosomal translocations involving the short arm of chromosome 2 (p15-p23) and the distal part of the long arm of chromosome 3 (q26-q27) are a rare but recurrent finding in patients with myeloid malignancies, and are assumed to be part of this spectrum of disorders. Thus far, however, these translocations have been poorly studied. Here, we present 21 new cases with myelodysplasia, acute myeloid leukemia or CML in blast crisis, which upon karyotyping showed the presence of a t(2;3). Furthermore, an extensive literature review disclosed 29 additional cases. Morphological, clinical and cytogenetic assessment revealed the typical hallmarks of 3q26/EVI1 rearrangements, that is, trilineage dysplasia and dysmegakaryopoiesis, poor prognosis and additional monosomy 7. Molecular cytogenetic analysis and PCR in selected samples indicated that in most cases the translocation indeed targets the EVI1 locus. Mapping of the chromosome 2 breakpoints confirmed the initially suspected cytogenetic breakpoint heterogeneity at the 2p arm.

We report on the clinical and cytogenetic data of a large family with an unbalanced insertion translocation (3;5)(q25.3;q22.1q31.3). Analysis of GTG-banded chromosomes demonstrated that unbalanced inheritance of a parental insertion translocation caused either a partial deletion or duplication 5q in this family. The derivative chromosomes were characterized further using microdissection and FISH with band-specific probes. The clinical picture of the proband with a partial deletion of chromosome 5 was characterized by moderate psychomotor retardation, mild facial dysmorphism, cleft palate, and single transverse crease. The family members with a partial duplication of chromosome 5 were borderline intelligent, had mild facial dysmorphism, a cardiac anomaly, and a high-pitched voice. The unbalanced carriers were compared with patients reported in the literature with a duplication or deletion of chromosome region 5q22.1 --> 5q31.3.

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