Typing of X chromosomes bearing Tabby allele in mouse preimplantation embryos by detection of a microsatellite marker.

Tabby (Ta) is a semidominat allele of the locus on the mouse X chromosome, which causes a characteristic coat pattern and developmental defects in endocrinic glands. To establish a method for identifying the X chromosome bearing the Ta allele in early preimplantation embryos, we performed PCR amplification of an X chromosomal microsatellite marker locus from preimplantation embryos obtained from mating between XO female and XY male mice. The microsatellite marker locus was shown to be polymorphic between X chromosomes bearing the Ta and wild-type alleles. The amplification of the marker locus from early preimplantation embryos demonstrated that the Ta locus can be correctly typed by this method from embryos as little as 2 cells.