PTBP2 and autism: This multi-method study then built the scientific case for (1) a mutation in HAR 426 affecting the gene CUX1; (2) a HAR mutation between DPYD and PTBP2 affecting PTBP2; and (3) two separate homozygous HAR mutations near GPC4. Finally, by analysing the genomes of consanguineous individuals with autism and looking for damaging mutations inherited from both parents but affecting the same locus (biallelic), they estimated that this may be the causative mechanism in 5% with a similar familial structure.