Exploring Genetics on the Web
In this presentation mutation is defined as random copying errors of genes or chromosome(s) along a genome’s long sequence of base pairs in an individual’s DNA sequence. Mutations are described as genetic markers because they are unique and can be traced back generations through inheritance. Haplotypes are a person’s individual footprint of all tested genetic markers and the difference of a single genetic marker delineates a distinct haplotype. The description in the text is very similar to the online description of the sickle cell allele and how it is the beneficial in preventing malaria but goes into better description of the symptoms. The blue marker ended up disappearing because the blue lineage didn’t reproduce overtime and in such a small population the allele frequency discontinued which is an example of genetic drift. Population genetics focuses not on individuals, but rather the total pattern of an entire biological population interested in defining the relative frequencies of different alleles , genotypes and phenotypes then seek to determine if any change in these frequencies have occurred overtime and if changes have occurred trying to explain them. The four mechanisms of evolution are mutation, natural selection, gene flow and genetic drift. The information from this link relates to the course in going further in depth to show genetic drift and cell biology.
A disease that is caused by an abnormality in an individual’s DNA is a genetic disorder. Genetic disorders abnormalities can delete, multiply or add genes or chromosomes in the DNA sequence.
*Single Gene Disorders: Smith-Lemli-Opitz Syndrome (SLOS)
Smith-Lemli-Opitz syndrome is caused by a mutation in the DHCR7 gene on chromosome 11, a single gene is affected. The disorder is inherited in an autosomal recessive pattern. SLOS is metabolic disorder and people affected are unable to make enough cholesterol to support normal growth and...