A single nucleotide point mutation (T>C) in exon 12 at position 2548 of the cDNA changes stop codon 764 TAA to glutamine codon CAA which restores the full open reading frame. This wild-type (coding) allele is found in 20 non-Black/6 strains. The T variant is only found in B6 and BTBR T+ Itprtf/J (Jax strain: 002282) strains. (J:245487)