heterozigózia

Heterozigozia refers to a genetic state in an individual where two different alleles are present for a particular gene. Alleles are different versions of the same gene, and they are located at the same position on homologous chromosomes. When an individual inherits one allele from each parent, and these alleles are different, the individual is said to be heterozygous for that gene. For example, if a gene controlling eye color has an allele for brown eyes (B) and an allele for blue eyes (b), an individual with the genotype Bb would be heterozygous for eye color.

In contrast, an individual who has two identical alleles for a gene is described as homozygous. For the eye color gene, a homozygous individual would have either BB (two brown eye alleles) or bb (two blue eye alleles). The presence of different alleles in a heterozygote can lead to various phenotypic expressions. Often, one allele, known as dominant, will mask the effect of the other, recessive, allele. However, in some cases, such as incomplete dominance or codominance, both alleles can contribute to the observable trait. Heterozygosity plays a crucial role in genetic diversity within a population and can influence an organism's susceptibility to diseases or its adaptation to environmental changes.