INTRODUCTION
Heredity is the physical or mental transfer of traits from parents to children. Genetics is the scientific study of how heredity is passed down from generation to generation. Gregor Mendel’s work in the 1860s started the science of genetics. In 1865, he reported his research on seven garden pea characteristics. Many scientists believed before Mendel’s discoveries that characteristics of parents mingled in each child. However, Mendel determined that each parent contributes genetic units (particles) to children. These genetic units are now called genes.
Polymers, such as DNA, are composed of repeated chemical units, much like beads in a chain. Nucleotides are DNA units that may be classified as A, T, G, or C. The genetic code is a sequence of nucleotides that contains information. This genetic information regulates life. This code specifies genetic terms that will be translated into fundamental biological activities; these fundamental terms are referred to as Genes. When all Genes are combined, they create the Genome (DNA) the scientific name of the software of life.
History
Branches of Genetics:
- Classical Genetic: concerned with the chromosomal theory of inheritance (a concept that genes are present in a linear manner on chromosomes). The relative position of genes can be determined by their frequency in offspring.
- Molecular Genetics: the study of genetic material; its structure, replication, and expression as well as recombinant DNA techniques (genetic engineering, human genome project).
- Evolutionary Genetics: the study of the mechanisms of evolutionary changes.
- Microbial Genetics: the genetical study of microbes.
- Myogenetics: the genetical study of fungi.
- Biochemical Genetics: the genetical study of biomolecules (DNA, RNA, proteins)
- Biometrical Genetics: a quantitative study of genetics
- Population genetics: the genetical study of populations
- Radiation Genetics: Study of the impact of radiation on the genetic material of an organism
- Eugenesis: application of genetic principles for the betterment of human beings.
- Quantitate Genetics: study the inheritance of polygenic characters which displays continuous variation this branch of genetics is also known as mathematical genetics.
- Cytogenesis: a combined study of cytology and genetics
- Euphenics: control of hereditary diseases i.e., inborn errors of metabolism.
- Genomics: this is the new branch or area of genetics that deals with the structure and functions of the genome in plants and animals.
