In this paper, researchers investigate the contribution of genetic variation to amino acid levels by performing single variant and gene-based tests of association between nine serum amino acids and 16.6 million genotyped and imputed variants in 8,545 non-diabetic Finnish men from the METabolic Syndrome In Men (METSIM) study.

In addition to the seven novel gene associations, five independent signals at established amino acid loci were identified, including two rare variant signals at GLDC, with glycine levels and HAL with histidine levels.