Based on Mendel’s experimental observation and conclusion on pea plants, he proposed four postulates including one that each phenotypical characteristic are controlled by a pair of unit factors also known as alleles that separate independently in gametes. Although Mendel’s contribution to genetics isn’t wrong, there are some exceptions of inheritances that do not follow Mendel’s principles. Non-mendelian inheritance traits include maternal effects, epigenetics, and extranuclear genes. What makes…
Our interest in the topic of Down syndrome (Trisomy 21) started when we heard about how many people are affected by this disease. The number of people affected by this disease in the United States alone is around 400,000 people. This genetic disorder is caused when a person is born with an extra copy of chromosome twenty-one. Down syndrome is recognized by things such as short stature, a distinctive palm crease, stubby fingers, mental retardation that can end up being serious, a wide gap between…
paper will go in more details about a complex interaction of environmental (exogenous and endogenous), including genetic, risk factors in developing malignant melanoma. It will touch on the familial melanomas occur in a familial setting related to mutation of the CDKN2A gene as that encodes p16.4 The purpose of this project is to concisely assess the anatomy and physiology, the epidemiology, risk factors, and in more detail about Malignant Melanoma. Before elaborating on Malignant Melanoma, let…
system (i.e. the immune system becomes susceptible to infections, improper clotting, etc.). The cause for the excessive production of cells is unknown but risk factors that can make children more susceptible to this disease involves various genetic mutations such as: Down syndrome, Neurofibromatosis type 1, mismatch repair deficiency…
Humans and their extinct relatives, Neandertals, both possess the same mutation that causes a null allele at the blood group gene, giving individuals the O blood type phenotype, and the allele’s frequency in both humans and sampled Neandertals suggests that the allele confers some advantage to its possessor and underwent positive…
1. Is it true that a homozygous dominant father and a homozygous recessive mother could give birth to a homozygous recessive child with the disorder phenotype? Explain. From the information provided, it can be determined that this statement is not true, as the offspring of this couple will not be homozygous recessive for the given trait. As both of the parents are homozygous for their respective alleles, every child would receive an allele from each parent, one being dominant (D) and the other…
Colon cancer is cancer of the large intestine (colon), the lower part of your digestive system. Most colon cancer cases begin as small, noncancerous or benign clusters of cells called adenomatous polyps. Over long periods time some of these polyps can potentially become colon cancers. Polyps may be small and can cause few, if any at all, symptoms. Because of this reason, doctors tend to recommend having regular screening tests to help prevent colon cancer by recognising and removing polyps…
Fibrosis? Cystic Fibrosis is a genetic disease that is one of the most common and lethal. The disease is usually noticeable in the victim by the age of 3 and impairs their ability to breathe and digest normally. This genetic disease is caused by a mutation of the CFTR gene (cystic fibrosis transmembrane conductance regulator). Everyone does have this gene, but only when it is mutated can it cause Cystic Fibrosis. Normally, the CFTR gene produces a protein whose job is to regulate salt and fluids…
large decrease in the size of an original population can eliminate a large amount of genes. 23. How does mutation increase genetic variation in a way that crossing over and independent assortment do not? This because during mutation selection removes deleterious alleles however, dangerous recessive alleles are preserved in heterozygotes and are reintroduced by mutations 24. How does mutation alter allele frequencies? are a continual source of genetic variation in…
syndromes. Lynch syndrome is due to germline mutations in the MMR system, including MLH1, MSH2, MSH6 and PMS2 genes, and in EPCAM gene, that cause high microsatellite instability and increase the risk of endometrioid, clear cell and undifferentiated carcinoma. Lynch syndrome is responsible of 5% of endometrial cancers and 1% of ovarian cancer cases, but high microsatellite instability is found in 30-40% of endometrial carcinomas, due to somatic mutations and MSH1 promoter methylation. The…