genotype
In a broad sense, the term "genotype" refers to the genetic makeup of an organism; in other words, it describes an organism's complete set of genes. In a more narrow sense, the term can be used to refer to the alleles, or variant forms of a gene, that are carried by an organism. Humans are diploid organisms, which means that they have two alleles at each genetic position, or locus, with one allele inherited from each parent. Each pair of alleles represents the genotype of a specific gene. For example, in sweet pea plants, the gene for flower color has two alleles. One allele codes for purple flowers and is represented by the uppercase letter F, whereas the second codes for white flowers and is represented by the lowercase letter f. A varied population of sweet pea plants could therefore feature three possible genotypes at this locus: FF, Ff, or ff. Each plant's genotype contributes to its phenotype, which, in this case, is the outward appearance of its flowers. A particular genotype is described as homozygous if it features two identical alleles and as heterozygous if the two alleles differ. The process of determining a genotype is called genotyping.
Further Exploration
Concept Links for further exploration
