A total of 150 infertile couples underwent chromosome analysis and genetic counselling before intracytoplasmic sperm injection (ICSI). Chromosomal abnormalities, including low-level sex chromosome mosaicism, were detected in 12% of the men and an unexpectedly high 6% of the women. Chromosomal abnormalities included gonosomal mosaicism in 13 cases, Robertsonian translocations in four males, auto...

Murine ovarian teratomas were used to determine recombination percentages for gene-gene and centromere-gene intervals. Data were obtained utilizing a recombinant inbred strain, LTXBJ, and a number of newly developed LT/SvEi congenic strains. --Centromere-gene recombination was measured at 11.3 & 1.2% for the centromere of chromosome 7 Gpi-1 interval and 15.8 2 2.4% for the centromere of chromos...

Preimplantation genetic diagnosis (PGD) for people suffering recurrent miscarriages is increasingly being performed worldwide. However, there is limited information on whether PGD can improve success rates in translocation carriers. We therefore compared pregnancy outcomes between PGD and natural pregnancy cases, reviewing the clinical research database. No improvement in the success rate at th...

9 Introduction Lejeune et al, in 1959 were the first to demonstrate that Down syndrome was due to an abnormality of an extra chromosome in the G group. This was subsequently confirmed to be chromosome 21. Other studies followed demonstrating that the characteristic appearance of Down syndrome could also be due to other aberrations involving chromosome 21. These included Robertsonian translocati...