Non-random distribution of mutations in the PHEX gene, and under-detected missense mutations at non-conserved residues

Thirty newly detected mutations in the PHEX gene are reported, and pooled w ith all the previously published mutations, The spectrum of mutations displ ayed 16% deletions, 8% insertions, 34% missense, 27% nonsense, and 15% spli ce site mutations, with two peaks in exon 15, and 17, Since 32.8% of PHEX a mino acids were conserved in the endopeptidases family, the number of misse nse mutations detected at non-conserved residues was smaller than expected, whereas the number of nonsense mutations observed at non-conserved residue s was very close to the expected number, Compared with conserved amino acid s, the changes in nonconserved amino acids may result in benign polymorphis ms or possibly mild disease that may go undiagnosed.