Human Genetics The study of heredity factors in humans. The human genetics had its basis by the rediscovery of Mendel's laws in 1900. The principles are known from the general genetics of plants, and animals also apply to humans. Human genetics encompasses the medical genetics, where the study of inherited diseases and chromosomal disorders have consequential practical applications in genetic counseling and prenatal diagnosis. Important areas are also genetic epidemiology and human genome project.
Each of our genes is part of cellekjernens deoxyribonucleic acid (DNA), and all these plants (genes) are organized in the 46 chromosomes present in each of the cells in the body. The 46 chromosomes are sex chromosomes, which are XX in females and XY in the mail, plus 22 pairs of chromosomes, which together are called autosomes. The woman is developing egg cells with 22 autosomes and one X-chromosome.
The man, on the other hand, develops sperm of two types: one type has 22 autosomes and one X chromosome; the other has 22 autosomes and one Y chromosome. An egg fertilized by an X sperm gives a girl, a Y-sperm at fertilization gives a boy.