Reciprocal chromosome translocation with transfer of centromeric heterochromatin in the domestic pig karyotype

摘要

Gustavsson, I. and Settergren, I. 1984. Reciprocal chromosome translocation with transfer of centromeric heterochromatin in the domestic pig karyotype. —Hereditas 100: 1–5 Lund, Sweden. ISSN 0018–0661. Received March 11. 1983A boar with normal sexual behaviour and normal semen picture but producing half the normal litter size was found to be the carrier of a rcp(7q-;llq+). Several of his daughters in commercial herds were reported to farrow small litters. The translocation was also found in the sire of the boar, which demonstrated a fairly normal fertility and had been used extensively for breeding work. One of the chromosome breakages had occurred proximally in the q arm of chromosome 11 close to the centromere, with the transfer of centromeric heterochromatin to the chromosome arm 7q-. There was a ring-shaped quadrivalent in male meiosis, indicating a preferential 2:2 segregation. All offspring demonstrated normal or balanced heterozygous karyotypes in a 1:1 ratio.