MLH1 and Ataxia: BLM has been reported to physically and/or functionally interact with a number of proteins, such as DNA damage checkpoint kinases ATM (Ataxia telangiectasia mutated) and ATR (ATM and Rad3-related) [6]; homologous recombination protein RAD51 recombinase [7]; mismatch repair protein MLH1 (MutL Homolog 1) and MSH6 (MutS Homolog 6) [8,9]; DNA replication checkpoint protein TopBP1 (topoisomerase-IIβ-binding protein 1) [10]; telomere-binding protein TRF2 (telomere repeat binding factor 2) [11].