In the rare circumstance in which neither one of the parents is a balanced
translocation carrier, there are commercially available FISH probes for the 22q11.2 deletion and also for the telomere of 11q which can identify the supernumerary chromosome in the karyotype as being derived from chromosomes 11 and 22.
A 22/22
translocation carrier with recurrent abortions demonstrated by a Giemsa banding technique.
Normal sperm in a 2;2 homologous male
translocation carrier. J Assist Reprod Genet 2012;29:665-8.
This report describes a selection process of embryos originating from a balanced three-way reciprocal
translocation carrier using array CGH.
There is a significant increased risk of giving birth to a child with Trisomy 21 when one parent is a Robertsonian
translocation carrier or of reciprocal translocations as they may produce balanced and unbalanced gametes during gametogenesis.
Pregnancy obtained after PGD was confirmed by prenatal diagnosis and balanced
translocation carrier was shown.
* Parenteral chromosome studies: If translocation is identified to rule out the
translocation carrier; since it carries a high recurrence risk for next child and in such case there are possibility of such risk to other family member of parent.
The balanced chromosomal
translocation carriers have increased risk for pregnancy losses or having children with mental or physical abnormalities because of unbalanced segmental chromosomal losses and gains.
A balanced reciprocal translocation is an exchange of material between two nonhomologous chromosomes, without loss or gain of material and balanced
translocation carriers are usually healthy and phenotypically normal.
Because
translocation carriers are, theoretically, at high risk of transmission of an unbalanced segregant to the blastomere, as many as 10 blastomeres will often be screened until one or two are deemed normal for the FISH probes in question.
Possible interchromosomal effect in embryos generated by gametes from
translocation carriers. Hum Reprod 2002; 17 : 3201-7.
Yet, there is undisputed evidence that the human male significantly affects the health of his children through sperm DNA in paternally mediated Mendelian genetic defects, chromosomal aberrations (e.g., paternal
translocation carriers), and aneuploid sperm (associated with 30-50% of Klinefelter, 80% of Turner, 5% of Down, and 100% of extra Y chromosome syndromes) (Blanco et al.