Genes – The Unit of Hereditary Information

Genes – The Unit of Hereditary Information
Introduction
Archibald Garrod discovered in 1902, that certain diseases were more prevalent among some families and were inherited as a recessive Mendelian trait.
Alkaptonuria
Alkaptonuria is a disease in which the urine contained a substace called “Alkapton” now known as “Homogentisic acid” which was immediately oxidizes to black when exposed to the air.
Causes

• He suggested that this disease occurred due to absence of an enzyme, which could break the “Alkapton” down to other products so it would not build up in the urine.
• He proposed that the condition was “inborn error of metabolism” which is occurring due to changes in the hereditary information, which must have occurred in one of the ancestors of a affected families.

Conclusion
He concluded that the inherited disorders might reflect enzyme deficiencies