beta-Thalassemia is one of the most common autosomal recessive single-gene disorders in Cyprus. Development of a noninvasive prenatal diagnostic (NIPD) assay for beta-thalassemia is based mostly on the detection of paternally inherited single nucleotide polymorphisms (SNPs) using the arrayed primer extension (APEX) method. Eleven SNPs with high degree of heterozygosity in the Cypriot population were selected and analyzed on 34 families and the informative SNPs were determined. The APEX assay was used on maternal plasma of seven families using the informative SNPs; paternal allele of the fetus was noninvasively detected in five families.

The development of a noninvasive method for detection of beta-thalassemia in the population of Cyprus is based on the detection of paternally inherited single nucleotide polymorphisms (SNPs) as well as beta-thalassemia (beta-thal) mutations. We selected 11 informative SNPs for the Cypriot population linked to the beta-globin locus. Two different approaches were used: allele-specific polymerase chain reaction (AS-PCR) and the arrayed primer extension (APEX) method. The AS-PCR approach is being standardized, and the method was applied in two families. The paternally inherited allele was noninvasively detected with the AS-PCR approach on maternal plasma. Some preliminary tests were performed with the APEX method on genomic DNA of parents carrying the beta-thal mutation.