OBJECTIVE: To directly study the meiotic segregation of a complex reciprocal translocation (CCR) as well as the occurrence of an interchromosomal effect. DESIGN: In situ sperm fluorescence in situ hybridization (FISH) analysis. SETTING: Department of Cytogenetics and INSERM research center. PATIENT(S): A male carrier of a balanced complex reciprocal translocation t(5;13;14)(q23;q21;q31). INTERVENTION(S): Sperm samples from the carrier and direct FISH analysis on sperm slide preparations. MAIN OUTCOME MEASURE(S): Meiotic segregation pattern determined on sperm nuclei and estimation of the incidence of unbalanced spermatozoa and an interchromosomal effect (ICE). RESULT(S): Only 27% of spermatozoa displayed a normal or balanced chromosome complement. The rate of unbalanced sperm was 69.4%, including different types of 3:3, 4:2, and 5:1 segregations. There was no evidence for the occurrence of an interchromosomal effect in autosomal chromosomes, but the gonosomes displayed a statistically significant increase in disomy rates. CONCLUSION(S): These results are consistent with the formation of a hexavalent configuration at the pachytene stage of meiosis and a high prevalence of imbalance production. The mechanisms of formation of CCRs must be examined with regard to these direct results and new molecular data on the formation of genomic rearrangements.
OBJECTIVE: To directly study the meiotic segregation of a complex reciprocal translocation (CCR) as well as the occurrence of an interchromosomal effect. DESIGN: In situ sperm fluorescence in situ hybridization (FISH) analysis. SETTING: Department of Cytogenetics and INSERM research center. PATIENT(S): A male carrier of a balanced complex reciprocal translocation t(5;13;14)(q23;q21;q31). INTERVENTION(S): Sperm samples from the carrier and direct FISH analysis on sperm slide preparations. MAIN OUTCOME MEASURE(S): Meiotic segregation pattern determined on sperm nuclei and estimation of the incidence of unbalanced spermatozoa and an interchromosomal effect (ICE). RESULT(S): Only 27% of spermatozoa displayed a normal or balanced chromosome complement. The rate of unbalanced sperm was 69.4%, including different types of 3:3, 4:2, and 5:1 segregations. There was no evidence for the occurrence of an interchromosomal effect in autosomal chromosomes, but the gonosomes displayed a statistically significant increase in disomy rates. CONCLUSION(S): These results are consistent with the formation of a hexavalent configuration at the pachytene stage of meiosis and a high prevalence of imbalance production. The mechanisms of formation of CCRs must be examined with regard to these direct results and new molecular data on the formation of genomic rearrangements.
Authors: Marta Olszewska; Tomasz Stokowy; Nijole Pollock; Nataliya Huleyuk; Andrew Georgiadis; Svetlana Yatsenko; Danuta Zastavna; Alexander N Yatsenko; Maciej Kurpisz Journal: Int J Mol Sci Date: 2020-06-26 Impact factor: 5.923