Optimal polymerase chain reaction amplification for preimplantation diagnosis in cystic fibrosis (∆F508)

Abstract

Objective: To evaluate direct polymerase chain reaction amplification of mutation on single embryo cells for the routine preimplantation diagnosis of cystic fibrosis. >Design: Direct polymerase chain reaction amplification of mutation was performed to identify the cystic fibrosis F508 mutation in human blood DNA, single lymphocytes, embryos, and embryo cells obtained by biopsy. Preimplantation diagnosis was performed for a couple who were heterozygous carriers of the F508 mutation. Setting: Laboratory for preimplantation diagnosis in a reproductive medicine unit. Main outcome measure: Correct diagnosis of homozygous normal, heterozygous, and homozygous abnormal DNA of the cystic fibrosis F508 mutation. Results: 45 blood samples (18 homozygous normal, 17 heterozygous, and 10 homozygous abnormal) and 204 single lymphocytes from known sources showed 100% amplification and were diagnosed correctly. 17 human embryos and 52 normal nucleated embryo cells obtained by single cell embryo biopsy also showed 100% amplification. After a miscarriage of the initial pregnancy (diagnosed at preimplantation to be homozygous normal) in the heterozygous carrier couple, fetal tissue was confirmed to be homozygous normal. Conclusion: Direct polymerase chain reaction amplification of mutation is a simple, fast, reliable test for the common cystic fibrosis mutation in blood DNA and single cells and should be applicable to routine programmes of general screening, maternal blood examination, and preimplantation diagnosis.