Epidemiologic studies reveal a strong correlation between increased FTO expression and single nucleotide polymorphism (SNP) risk genotypes in various cancers, such as breast cancer[43] and melanoma.[44] Notably, a negative association between the FTO rs9939609 T allele and obesity was found in childhood ALL survivors.[45] Therefore, upregulation of FTO is potentially caused by the aberrant distribution of SNPs in T‐ALL. This evidence concerns the gene FTO and obesity due to melanocortin 4 receptor deficiency.