Galactosemia in Russia: molecular characteristics, neonatal screening, verifying diagnostics
Classic galactosemia (OMIM 230400) is an inherited defect of galactose metabolism caused by mutations in the galactose-1-phosphate uridyltransferase gene (GALT). The biochemical consequence of GALT deficiency is abnormally high concentrations of galactose and its metabolits in body tissues and fluids. Classical galactosemia may result in life threatening crisis in the early neonatal period. Early diagnosis of galactosemia permits to avoid seriously for child. Newborns may be reliably diagnosed in time only through mass screening. Many countries have included screening for galactosemia in their national screening programs. Mass screening of newborns for galactosemia in Russia has been available since 2006. Obviously, the verifying diagnostics is necessary part of any screening programs. The aim of this study is the development of the protocol for verifying diagnostics of galactosemia in Russian population. Based on biochemical and molecular-genetics investigations we conclude that verifying diagnostics of galactosemia must consist of both the measure of galactose-1 -phosphate uridyltransferase activity in whole blood and DNA-analysis of GALT for common mutations and polymorphisms. Using all received data, we propose the improved algorithm for verifying diagnostics of classical galactosemia in Russian population