Tra1 belongs to the phosphoinositide-3-kinase-related kinase (PIKK) family, which includes ataxia telangiectasia mutated (ATM; Tel1 in S. cerevisiae), ataxia telangiectasia, and Rad3 related (ATR; Mec1 in S. cerevisiae), the DNA-dependent protein kinase catalytic subunit (DNA-PKc), mammalian target of rapamycin (Tor1 and Tor2 in S. cerevisiae), and SMG-1 (suppressor with morphological effect on genitalia family member) (Smith and Jackson 2003; Hill and Lee 2010; Shiloh and Ziv 2013). The gene discussed is ATR; the disease is telangiectasis.