How did Sir Archibald Garrod help establish the study of inborn errors of metabolism?

In 1908, British physician Sir Archibald Garrod fundamentally advanced the field of biochemical genetics by introducing the concept of inborn errors of metabolism.12

Garrod postulated that certain hereditary conditions—specifically alkaptonuria, pentosuria, albinism, and cystinuria—were caused by defects in specific biochemical pathways. He theorized that these diseases resulted from the diminished activity or complete absence of specific enzymes, which prevented the normal transformation of metabolites.21

By suggesting that these inherited disorders were linked to molecular actions at the cellular level, Garrod provided a foundational framework for understanding how genetic mutations lead to metabolic disease. His work established a conceptual bridge between genetics and medicine, later influencing the one gene-one enzyme principle, which confirmed that mutated genes produce defective enzymes with altered or absent function.234