Exclusion of beta-thalassaemia by biopsy and DNA amplification in mouse pre-embryos

Exclusion of beta-thalassaemia in mice was undertaken by pre-implantation DNA diagnosis. Biopsies of approximately five cells were obtained from mouse pre-embryos. DNA prepared from this material was amplified by the polymerase chain reaction (PCR), enabling identification of the normal beta-major globin gene in 11 out of 20 cases where it was known to be present. The expected negative result was obtained in 14 out of 16 homozygous thalassaemic embryos, with two false positives. Results are promptly available following PCR, thereby facilitating re-implantation of embryos which have had homozygous beta-thalassaemia excluded. The mouse model illustrates a useful approach to pre-implantation diagnosis of genetic disease in the human.