Fig. 1

The feline GNPTAB structure and DNA sequencing results surrounding the c.2644C > T variation in exon 13 which is predicted to produce a GNPTAB protein without a β subunit. a A phenotypically healthy littermate (7161), showing homozygosity for cytosine (c.2644C, arrow). b A ML II affected kitten (7160), revealing homozygosity for a C > T substitution (c.2644 T), which will change the codon CAG (for glutamine) to TAG (a stop codon) at GNPTAB protein position 882 (p.Gln882*). c The clinically healthy tom cat (4977) of the ML II affected kittens, displaying both wild type and mutant allele (c.2644Y, heterozygous status). d Feline GNPTAB protein domain structure (adopted from human construct with 91% amino acids homology between human and cats). e The ML II affected cats with the p.Gln882* variant predicted to produce a GNPTAB enzyme with a truncated α subunit and without β subunit