Autosomal trisomy 20 (61,XX,+20) in a malformed bovine fetus

A 240-day-gestation female bovine fetus with severe anasarca, palatoschisis , cheiloschisis, mild cranioschisis. and a flattened facies was collected a t a slaughterhouse, and a fibroblast line was established from the fetal sk in. Chromosome preparations were Q-banded, and chromosome counts were taken that indicated the presence of 61 chromosomes in cells of the fetus (the n ormal diploid number for domestic cattle is 60). Q-band karyotypes were con structed, and Q-band analysis revealed the presence of three copies of chro mosome 20. Trisomy 20 (61,XX,+20) was confirmed through the use of two-colo r fluorescence in situ hybridization of bovine bacterial artificial chromos ome clones that were specific to chromosome 20 and the X chromosome.