This ENU-induced mutation was isolated in a screen at the University of Pittsburgh. It is a subline of b2b1702Clo. The molecular lesion for this subline is an A to T substitution at coding nucleotide position 289 in exon 3 of the cDNA (c.289A>T, NM_023493). This changes the isoleucine residue to phenylalanine at position 97 in the encoded protein (p.I97F).