Analyte testing for SCAD disease (SCADD) in blood and urine is complicated by the high allele frequency of two ACADS variants (c.625G>A, p.Gly209Ser (rs1799958) and c.511C>T, p.Arg171Trp (rs1800556) (NM_000017.3)). The gene discussed is ACADS; the disease is short chain acyl-CoA dehydrogenase deficiency.