A novel compound heterozygous mutation in Werner syndrome results in WRN transcript decay.

BACKGROUND: Werner syndrome (WS) is a rare autosomal recessive progeroid disorder caused by mutations of the WRN gene encoding a protein of the RecQ-type family of DNA helicases. OBJECTIVES: To develop a rapid and simple reverse transcription-polymerase chain reaction (RT-PCR) strategy for mutation analysis of the WRN gene, to identify pathogenic mutations in a German patient with WS and to determine the effects of the pathogenic mutations on WRN mRNA stability. METHODS: Allele-specific RT-PCR, semiquantitative RT-PCR, DNA sequencing. RESULTS: We describe a novel and rapid RT-PCR-based method for mutation analysis in WS and report a German patient with WS carrying a previously reported (1396delA) as well as a novel nonsense mutation (2334delAC) of the WRN gene. By semiquantitative RT-PCR analysis we demonstrate that this compound heterozygous genotype leads to WRN transcript decay. CONCLUSIONS: In previous studies WS was primarily attributed to a loss of function of stable truncated WRN gene products. Our findings indicate that mutations can also lead to markedly decreased WRN transcript stability.