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

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.