Sex chromosome mosaicism in man

Mosaicism, chimerism and sex-chromosome inactivation.

Sex chromosome mosaicism in couples undergoing intracytoplasmic sperm injection.

BACKGROUND Several studies have shown an increased frequency of constitutional chromosome aberrations in male and female partners of couples examined prior to ICSI. We conducted a cohort study to determine whether there was an increase in numerical sex chromosome mosaicism among couples undergoing ICSI compared with fertile couples. METHODS Cytogenetic investigations were performed in 228 fem...

Origin of sex chromosome monosomy in man.

There are striking contrasts when the apparent origin of the 45,X anomaly is compared with most trisomic conditions, and recent work gives interesting clues to the causes of sex-chromosome monosomy. Except for a small proportion of cases arising from secondary non-disjunction of primary trisomic subjects-or cells-and a further group of segregational examples arising from centric fusion heterozy...

Sex Chromosome Mosaicism and Hybrid Speciation among Tiger Swallowtail Butterflies

Hybrid speciation, or the formation of a daughter species due to interbreeding between two parental species, is a potentially important means of diversification, because it generates new forms from existing variation. However, factors responsible for the origin and maintenance of hybrid species are largely unknown. Here we show that the North American butterfly Papilio appalachiensis is a hybri...

Effect of gonadotropins on chromosome aneuploidy, chromosome mosaicism & sex ratio in mouse preimplantation embryos.

BACKGROUND & OBJECTIVE There are potential risks of major birth defect in IVF (in vitro fertilization) pregnancy as well as IVF-ICSI (intra cytoplasmic sperm injection) pregnancies in comparison with naturally conceived human pregnancies. This increase risk could be due to either gonadotropins used for ovarian stimulation or in vitro culture conditions or multiple pregnancy or combinations of a...