Preimplantation genetic diagnosis of P450 oxidoreductase deficiency and Huntington Disease using three different molecular approaches simultaneously.

PURPOSE: Description of the confluence of different molecular techniques to detect three different mutations in one cell. The man carries a 20 base pair insertion in exon 12 of the POR gene (c.1551_1552ins20), and the woman carries a point mutation in exon 8 of the POR gene (c.859G>C) plus a triplet repeat expansion in the HTT gene.

METHODS

Huntington Disease (HD) had to be diagnosed using short tandem repeat (STR) markers linked to the HTT gene. The mutation c.1551_1552ins20 was analyzed by fragment size and c.859G>C was minisequenced. Furthermore, STR markers linked to the POR gene were included to support the diagnosis of P450 oxidoreductase (POR) deficiency.

RESULTS

Nine embryos were diagnosed in total: three as POR deficiency affected, two as HD affected, one as POR deficiency and HD affected, and two as carriers of the paternal POR deficiency mutation and healthy for HD. These two last embryos were transferred but no pregnancy was achieved.

CONCLUSIONS

A successful procedure combining direct and indirect methods for the detection of three different mutations in a single cell has been achieved for the first time.