Interaction of Genes
Genes act by controlling cellular chemistry. Early in the twentieth century, Archibald Garrod, an English physician, made the first observation supporting this insight. Garrod noted that several recessive human diseases show defects in what is called metabolism, the general set of chemical reactions taking place in an organism. This observation led to the notion that such genetic diseases are […]
Human Pedigree Analysis
Human matings, like those of experimental organisms, provide many examples of single-gene inheritance. However, controlled experimental crosses cannot be made with humans, and so geneticists must resort to scrutinizing medical records in the hope that informative matings have been made (such as monohybrid crosses) that could be used to infer single-gene inheritance. Such a scrutiny of records […]
Autosomal inheritance in humans
Human matings, like those of experimental organisms, show many examples of the inheritance patterns described above. Because controlled experimental crosses cannot be made with humans, geneticists must resort to scrutinizing records in the hope that informative matings have been made by chance. Such a scrutiny of records of matings is called pedigree analysis. A member […]
Mendel’s law of Independent Assortment
Mendel began working with the pair of characters,those were seed shape and seed color. The cross in which two traits are studied at same time is dihybrid. As we know the monohybrid cross for seed color (Y/y x Y/y), which gave a progeny ratio of 3 yellow:1 green. The seed shape phenotypes were round (determined by allele R) and […]
Mendel’s law segregation
Mendel’s model for the pea-color example, translated into modern terms, was as follows 1. A hereditary factor called a gene is necessary for producing pea color. 2. Each plant has a pair of this type of gene. 3. The gene comes in two forms called alleles. If the gene is phonetically called a “wye” gene, then the […]
Single Gene Inheritance
The genetic approach to understanding any biological property is to find the subset of genes in the genome that influence that property, a process sometimes referred to as gene discovery. After these genes have been identified, their cellular functions can be elucidated through further research. There are several different types of analytical approaches to gene discovery, but one […]
Mendel’s pioneering work
The first-ever analysis of single-gene inheritance as a pathway to gene discovery was carried out by Gregor Mendel. His is the analysis that we shall follow as an example. Mendel chose the garden pea, Pisum sativum, as his research organism.The choice of organism for any biological research is crucial, and Mendel’s choice proved to be a good one […]