Poikiloderma with neutropenia: a novel C16orf57 mutation and clinical diagnostic criteria

A new syndrome with poikiloderma was described by Clericuzio et al. in 1991. They reported 14 Navajo native Americans, including eight siblings, developing in the first year of life an erythematous rash, which started on the limbs and spread over the trunk and the face. This rash evolved into poikiloderma. All patients had recurrent bacterial infections. First published as Navajo poikiloderma this syndrome is now known as poikiloderma with neutropenia (PN, OMIM 604173). The inheritance is autosomal recessive, and mutations in a new gene, C16orf57, were recently described in two kindreds. Because of the phenotypic overlap between Rothmund-Thomson syndrome (RTS) and PN, a few patients have been reclassified as mutations in the RECQL4 gene for RTS were absent. (2-5) Until now 27 patients have been described with clinical PN. (1-3,5-8) Here, we report the sixth family with PN outside the Navajo population. We found the previously unreported mutation c.243G > A, p.W81X in the C16orf57 gene, thus confirming the relation of this gene to the disease. (2,6) Because the molecular genetic diagnosis is not always available, we propose clinical and laboratory diagnostic criteria for PN.