In this article we will discuss about the examples of genetic linkage in humans. Also learn its clinical applications. 1. Nail-Patella Syndrome and ABO Blood Groups: This genetic linkage has been demonstrated by Reneisck and Lawler (1955). The nail- patella syndrome or hereditary onychosteodysplasia is characterised by a constellation of abnormalities. The nail dystrophy is variable, ranging from a triangular [...]
The following points highlight the top five criteria for genetic polymorphism. They are: 1. Selection 2. Mutation and Mutation Rates 3. Genetic Drift 4. Migration Pressure or Gene Flow 5. Meiotic Drive. Criteria # 1. Selection: Selection is the non-random or selective reproduction of genotypes. The elucidation of the selective forces which may have given rise to any particular polymorphism [...]
In this article we will discuss about:- 1. Meaning of Crossing Over 2. Frequency of Crossing Over 3. Factors 4. Molecular Mechanism. Meaning of Crossing Over: Crossing over may be defined as an interchange of corresponding chromosomal parts between members of a homologous chromosome resulting in a recombination of genes. One, two or more fragments may be interchanged during crossing [...]