Analysis of Recql4 helicase deficient mice

Abstract

It has been suggested that Recql4 gene is the responsible gene for a subset of Rothmund-Thomson syndrome (RTS) cases, but until now there has been no animal model to confirm this. It was reported that a knockout mice in which the Recql4 gene is disrupted at exons 5-8 exhibited embryonic lethality at embryonic day 3.5-6.5. We generated a helicase activity-inhibited mouse by replacing the exon 13 of Recql4 with a targeting vector, which is one of the coding exons of the consensus RecQ-helicase domain. This domain is the primary site of mutations that have been identified in RTS patients. The mutant mice are viable, but exhibit severe growth retardation and abnormalities in several tissues, and embryonic fibroblasts show a defect in cell proliferation. We compared the abnormalities in the Recql4-deficient mice with those in RTS patients. As a result, it was suggested that defects in the Recql4 gene may indeed be responsible for RTS. [J Radiat Res 44:405 (2003)]