Biochemical Screening Era era
During the Biochemical Screening Era (1952-1974), population-level newborn screening and enzymology emerged as the primary means to detect inherited metabolic disorders, with public health laboratories standardizing assay protocols and establishing mass screening workflows. Robert Guthrie pioneered population screening for phenylketonuria with the Guthrie test in the early 1960s, demonstrating the feasibility of universal neonatal testing. Concurrently, William Nyhan and Michael Lesch contributed critical insights into inborn errors of metabolism, exemplified by Lesch-Nyhan syndrome described in the 1960s, which linked specific enzymatic defects to clinical phenotypes. Together, Guthrie's screening innovations and the era's biochemical investigations helped institutionalize screening infrastructures and set the standards for future diagnostic expansions.
Pathway–Genotype Integration era
Charles R. Scriver and David Valle emerged as central figures in the pathway-genotype integration of inherited metabolic diseases during 1975-1995, reframing clinical presentations as discrete biochemical blocks within defined pathways. Scriver's group helped establish the biochemical genetics framework and, together with colleagues, co-edited The Metabolic and Molecular Bases of Inherited Disease, codifying how gene lesions map to enzymatic steps and pathway-level phenotypes. Valle contributed by elucidating molecular pathogenesis and linking specific mutations to enzyme defects and metabolic blocks through biomarkers and pathway logic, advancing nosology toward molecular mechanisms. The work of William Nyhan on Lesch-Nyhan syndrome illustrated genotype–pathway–phenotype correlations in purine metabolism, while newborn screening pioneers such as Robert Guthrie helped operationalize pathway-based diagnosis through early biomarker profiling.
Omics-Driven Precision Medicine era
John J.P. Kastelein [1] is affiliated with Harvard University [3] and the University of California, San Francisco [4] during this era. His key contribution was identifying mutations in ABC1 in Tangier disease [6] and familial high-density lipoprotein deficiency [6], as described in the 1999 paper Mutations in ABC1 in Tangier disease and familial high-density lipoprotein deficiency [6], establishing the genetic basis for inherited lipid disorders and enabling genotype-informed diagnosis in the omics-driven era. Stephen W. Scherer [2] is affiliated with Harvard University [3] and the Massachusetts Institute of Technology [5] in this era. His contributions to understanding Tangier disease [6] and familial high-density lipoprotein deficiency [6] illustrate how early genotype-based discoveries mapped variants to lipid pathways and laid groundwork for genotype-guided therapeutic strategies in omics-driven precision medicine.