Preimplantation and prenatal genetic diagnosis of aromatic L-amino acid decarboxylase deficiency with an amplification refractory mutation system-quantitative polymerase chain reaction

Abstract

Objectives: To develop a diagnostic platform for preimplantation genetic diagnosis (PGD) and prenatal genetic diagnosis (PND) to prevent births of aromatic L-amino acid decarboxylase deficiency (AADC) patients.

Materials and methods: Five Taiwanese families carrying AADC were enrolled. A novel technique, amplification refractory mutation system-quantitative polymerase chain reaction (ARMS-qPCR), was developed for both of PGD and PND. For PGD, blastomere biopsies of day-3 cleavage-stage embryos were subjected to ARMS-qPCR. Villi, cultured amniocytes, or both were used to confirm the PGD result; this approach could also be used as the sole method for PND after in vivo conception).

Results: Unaffected live births were achieved in four of the five families, except one with ongoing PGD. The ARMS-qPCR correctly classified blastomeres (from day-3 cleavage-stage embryos) as affected (homozygous mutant), carrier (heterozygous for mutant and wild-type alleles), or normal (homozygous wild-type) within 1 working day.

Conclusions: To our knowledge, this is the first report of successful PGD of AADC. The molecular technique we devised (ARMS-qPCR) was applicable for PGD as well as PND of AADC. Furthermore, it has great potential for similar applications in other monogenic disorders.