A genotype is an individual's collection of genes. It can also refer to the two alleles inherited from a particular gene. Dominant is spoken of as the relationship between two versions of a gene. Each individual receives two versions of each gene, known as alleles, one from each parent. If the alleles of a gene are different, the allele that is expressed is the dominant gene. The effect of the other allele, called recessive, is masked. According to Mendel's laws, if the color blonde is the dominant gene, it is likely that if you have a child it is blonde, if you have two at least one is; if you have 3, two are and if you have four, three are. It speaks of pure gene or pure line to the offspring of one or more individuals of identical genetic constitution, obtained by self-fertilization. They are homozygous individuals for all their characters.