Risk evaluation of carriers with chromosome reciprocal translocation t(7;13)(q34;q13) and concomitant meiotic segregation analyzed by FISH on ejaculated spermatozoa.

摘要: We performed the segregation analysis of a relatively large pedigree t(7;13)(q34;q13) carriers together with sperm karyotype one carrier using tri-color fluorescence in situ hybridization (FISH) method. The risk assessments for unfavorable pregnancy outcomes series 36 pregnancies eight reciprocal chromosome translocation (RCT) couples were estimated directly from after ascertainment correction. individual probability rate unbalanced child was predicted according to Stengel-Rutkowski and co-workers. karyotypes form monosomy 7q34-->qter trisomy 13q13-->qter detected among stillborn/early death newborns holoprosencephaly (HPE), cyclopia other malformations. Based on clinical description unkaryotyped stillbirth progeny, it can be assumed that phenotype distinctions connected 2:2 (monosomy 7q 13q) 3:1 as interchange 13 (Patau syndrome). Probability rates miscarriages, stillbirth/early 12.9 +/- 6% (4/31) 29 8.2% (9/31), respectively. results meiotic pattern indicated spermatozoa about 60%, unusual high (29.4%) segregant (i.e., 13.4% tertiary 16% segregation). Adjacent-1 followed 23.5% adjacent-2 7.2% analyzed spermatozoa. gametes comparison number miscarriages suggests strong selection against chromosomal constitutions during fetal development. It corresponds very small (about 0.3%) viable progeny maternal carriers. This knowledge used genetic counseling families similar RCT ascertained different way.