Preimplantation genetic diagnosis of X-linked adrenoleukodystrophy with gender determination using multiple displacement amplification

Abstract

Objective: To evaluate the use of multiple displacement amplification (MDA) for whole genome amplification in the preimplantation genetic diagnosis (PGD) of X-linked adrenoleukodystrophy.

Design: MDA was used to amplify the whole genome directly from a single blastomere. MDA products were used for polymerase chain reaction (PCR) analysis of two polymorphic markers flanking the ABCD1 gene and a new X/Y marker, X22, to sex embryos in an X-linked adrenoleukodystrophy PGD program.

Setting: Fertility and gynecology private center in Alicante, Spain.

Patient(s): A couple in which the wife is a carrier of the ABCD1 gene mutation (676A-->C) that was previously identified in her family.

Intervention(s): MDA of single blastomere and PCR tests for PGD.

Main outcome measure(s): The ability to analyze single blastomeres for X-linked adrenoleukodystrophy using MDA.

Result(s): The development of an MDA-PGD protocol for X-linked adrenoleukodystrophy allowed for the diagnosis of five embryos. These were biopsied on day 3 of culture and analyzed. One embryo was an affected male and one embryo was a female carrier. Three healthy female embryos were transferred 48 hours after biopsy. Unfortunately, no pregnancy was achieved.

Conclusion(s): The MDA technique is useful for overcoming the problem of insufficient genomic DNA in PGD and allows the simultaneous amplification of different targets to perform a diagnosis of any known gene defect and a sexing test by standard methods and conditions.