DNA-TEMPLATE AMPLIFICATION GENETIC-STUDIES ON ARCHIVAL HUMAN PREIMPLANTATION BIOPSIED MICROTUBED CELL SAMPLES

Biopsied cell samples can remain in storage following an initial, uneq uivocally successful preimplantation genetic diagnosis (PGD). The fide lity of the DNA template for polymerase chain reaction (PCR) amplifica tion of microtubed human preimplantation embryonic cells stored at -70 degrees C for extended periods of time (6 months to 4 years) has been assessed. PCR protocols and specific nested primer sets for the beta- globin, ZP3 and CA repeat motif successfully used for previous human e mbryo PGD research were employed for these studies. The results show t hat the DNA template of microtubed biopsied blastomere and mural troph ectoderm cell samples stored for periods of up to 4 years may be succe ssfully amplified by PCR. Specific gene sequences were able to be anal ysed at the 1-2 or 3-5 biopsied cell level with a 71-100% success rate . Analysis of DNA fragments amplified from the CA dinucleotide repeat locus showed that in 8/9 samples both alleles were amplified at the ce llular level. No DNA contamination was detected in the stored microtub ed samples, or in the experimental controls.