Furthermore, the smaller size of ATM variants cDNA overcomes the cargo limit of approved gene therapy vectors, improving the efficiency of viral particles production and infection efficiency compared with the whole ATM gene, as reported by Carranza et al., who constructed a lentiviral vector containing a full-length ATM capable of rescuing AT deficiencies, but with a low transduction efficiency [91]. The gene discussed is ATM; the disease is ataxia telangiectasia.