Heterosynapsis in a heterozygous fertile boar carrier of a 3;7 translocation

• Published in: Chromosoma Vol. 97; no. 1; pp. 26 - 32
• Main Authors: GABRIEL-ROBEZ, O, JAAFAR, H, RATOMPONIRINA, C, BOSCHER, J, BONNEAU, J, POPESCU, C. P, RUMPLER, Y
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01-01-1988; Springer Verlag
• Subjects: Animals; Biological and medical sciences; Chromosome Banding; Cytogenetics; Fundamental and applied biological sciences. Psychology; Genetics of eukaryotes. Biological and molecular evolution; Heterozygote; Karyotyping; Life Sciences; Meiosis; Microscopy, Electron; Mitosis; Semen - analysis; Swine - genetics; Synaptonemal Complex; Translocation, Genetic; Vertebrata; Chromosomal aberration; Heterozygozity; Chromosome pairing; Synaptonemal complex; Pig; Vertebrata; Mammalia; Transmission electron microscopy; Spermatocyte; Fertility; Cytogenetics; Abnormal chromosome; Artiodactyla; Ungulata; Pachytene; Chromosome translocation; GENETIQUE ANIMALE
• ISSN: 0009-5915; 1432-0886
• DOI: 10.1007/BF00331792

Silver-stained synaptonemal complexes (SCs) in surface-spread pachytene nuclei from a boar, heterozygous for a reciprocal translocation, were analysed by electron microscopy. In such heterozygotes, cross-shaped quadrivalent configurations are expected to form in order to maximize homologous pairing. Contrary to the classical, expected cross-shaped configuration, heterosynapsis was often observed, with asymmetrical association in the lateral elements of the non-homologous partners of the quadrivalents. This heterosynapsis is assumed to be a mechanism preventing spermatocyte loss, but inducing a secondary segregational type of impairment of fertility due to foetal wastage leading to reduced prolificacy.