Archibald garrod Postulated that recessive metabolic disorders resulted fror the inheritance of a defective enzyme from each parent Garrods tetrad: alkaptonuria, cystinuria pentosuria, albinism Phenylalanine Tyros p-Hydrowylphenylpyruwc acid ogenic acd Urine samples from patient +× Homogentsic acid ox 1857-1936 British physician with alkaptonuria. Left (freshly Professor Oxford University voided); right (after 24 h at RT) Maleylacetoacetc acid Published Inborn Errors of Metabolism" in 1908 OH HO OH Cystine stone in the urinary bladder OH O Xylulose accumulates in the urine Cystinuria (caused by defects in the SLC3A1 of patients with pentosuria. and SLC7A9 transporter genes) (caused by L-xylulase deficiency) Albinism (caused by a deficiency of tyrosinase, a enzyme required for the synthesis of melanin)Archibald Garrod 1857- 1936; British physician Professor Oxford University; Published Inborn Errors of Metabolism” in 1908 Postulated that recessive metabolic disorders resulted from the inheritance of a defective enzyme from each parent. Garrod’s tetrad: alkaptonuria, cystinuria, pentosuria, albinism Urine samples from patient with alkaptonuria. Left (freshly voided); right (after 24 h at RT) Albinism (caused by a deficiency of tyrosinase, a enzyme required for the synthesis of melanin) Cystinuria (caused by defects in the SLC3A1 and SLC7A9 transporter genes) Xylulose accumulates in the urine of patients with pentosuria. (caused by L-xylulase deficiency)