NASPGHAN recommends using serum alanine transaminase (ALT) to screen children, starting at the age of 9–11 years, who are obese or who are overweight, with additional risk factors including central adiposity, insulin resistance, pre-diabetes or diabetes, dyslipidemia, sleep apnea, or a family history of NAFLD. The gene discussed is GPT; the disease is sleep apnea syndrome.