Distinct forms of a gene, arising from variations in the DNA sequence at a specific locus, are a fundamental concept in genetics. These variations can lead to observable differences in traits, such as eye color or blood type. For example, the gene that determines blood type in humans exists in several forms, each coding for a slightly different protein that ultimately determines whether an individual has type A, B, or O blood.
The existence of multiple forms is crucial for genetic diversity within a population. This diversity allows populations to adapt to changing environmental conditions and increases their resilience to diseases. Historically, recognizing these different forms was a key step in understanding inheritance patterns and the mechanisms of evolution. The study of these variations has also been instrumental in identifying genes associated with diseases and developing personalized medicine approaches.