Postmortem molecular analysis to SIDS victims

Abstract

In the present report, our recent molecular analyses to SIDS victims are introduced. The majority of congenital central hypoventilation syndrome patients carried the polyalanine repetitive expansion on exon 3 of PHOX2B. In contrast to the presence of the expansions in all clinically diagnosed CCHS patients, no abnormalities of the gene sequence were evident in a total of 87 SIDS cases. We finally concluded that CCHS should be too rare to be involved in SIDS. For long QT syndrome, a total of six non-synonymous substitutions were detected from direct sequencing of the responsible ion channel genes such as KCNQ1, KCNH2, and SCN5A in specimens from the victims. We therefore considered that SIDS might be partly explainable by fatal arrhythmia. Postmortem molecular analysis is not omnipotent in disease diagnosis, but this approach is effective for searching for disorders in which mainly physiological dysfunction is exhibited.