More than 20 human ATG genes are predicted to have functional uORFs. (A) The number of active canonical uORFs initiated with an AUG start codon for ATG genes predicted by a machine learning algorithm [25]. ATG genes are classified into 5 groups, including those encoding components of the ULK1 complex, the PtdIns3K complex, the ATG9 trafficking system, the ATG12 Ubl conjugation system, and the Atg8-family Ubl conjugation system. ATG genes with no active canonical uORFs are not shown. (B) Composition analysis of uORFs (initiated with AUG or near-cognate start codons) in ATG genes predicted by a machine learning algorithm [25]. ATG genes with no active uORFs are not shown. (C) The frequency of AUG start codons and near-cognate start codons of predicted positive uORFs in all ATG genes. (D) Ultra-rare variants (singletons) from the Exome Aggregation Consortium (ExAC) catalog v.1 that are associated with predicted active uORFs of ATG genes are counted [25,46]. The composition of uORFs (initiated with AUG and near-cognate codons) that are associated with singleton variants are analyzed. PtdIns3K, phosphatidylinositol 3-kinase; Ubl, ubiquitin-like.