POC1B Mutations in Families Affected by COD or CRD
(A) Sanger sequencing showed the segregation of the homozygous missense mutation M1 (c.317G>C [p.Arg106Pro]) in family A and mutations M2 (c.199_201del [p.Gln67del]) and M3 (c.810+1G>T) in family B.
(B) mRNA RT-PCR studies showed a normal 421 bp product and aberrant 387 and 271 bp products lacking exon 7 and exons 6 and 7, respectively. The 387 and 271 bp cDNA deletions result in the predicted truncated POC1B products p.Val226Glyfs∗30 (c.677_810del) and p.Phe188Aspfs∗73 (c.561_810del), respectively.
(C) Evolutionary conservation of amino acid residues Gln67 and Arg106 in POC1B. The glutamic acid at position 67 is moderately conserved, whereas the arginine at position 106 is completely conserved among the listed species. Identical amino acids are indicated in black boxes, and conserved residues are indicated in gray boxes.