GJB2 and phenylketonuria: A modified UMI-based NGS approach, validated originally using Sanger sequencing for variants causative of Wilson disease (ATP7B)[89], has also been developed for NIPD of various monogenic conditions with pathogenic variants causative of autosomal recessive non-syndromic hearing loss (GJB2, GJB3, SLC26A4, RNR1, TRNL1, and COX1)[90,91], β-thalassaemia (HBB)[92,93], phenylketonuria (PAH)[94,95], and methylmalonic acidaemia cb1C type (MMACHC)[96].