Essay About Heterozygous Carriers And Autosomal Recessive Disorder

Genetic Disorders
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Genetics Disorders
Autosomal Recessive Disorder
Cystic Fibrosis
Autosomal recessive disorder that encodes for a protein called Cystic fibrosis conductance regulator which causes an ion imbalance in the body
Symptoms: excessive salty sweat, sticky mucus, digestion problems, respiratory problems
Health problems associated with CF include:
-Sticky mucous can cause infection
-Excessive loss of NaCl (through sweat)
-Pancreatic + intestinal issues resulting in digestion problems
Treatment:
-Enzymatic Digestive aids
-Nasal spray (DNAase)
-Antibiotics to combat possible respiratory bacterial infections
Probability of CF contraction:
1/25 individuals are heterozygous carriers
1/25 x 1/25 x 1/4 = 1/2500
Sickle-cell anemia
Autosomal recessive disorder that results in deformed hemoglobin-substitution of glutamic acid by valine
Ramifications:
-Shortened lifespan of red blood cell which results in anemia (not enough red blood cells)
-Oddly shaped cells clump resulting in poor circulation=impaired tissue and organ function, susceptibility to infection etc.
The body tries to compensate for the anemic conditions by generating more red blood cells but this results in deterioration of bone marrow
Pleiotrophy
Sickle cell anemia is an example of pleiotrophy 1 genotype results in more than 1 phenotype
Benefits of Sickle-Cell anemia
-Increased resistance to malaria
Therefore heterozygous individuals contain some benefits against malaraia but produce normal erythrocytes, example of heterozygous advantage
Phenylketonuria (PKU)
Decrease in the enzyme phenylalanine hydroxylase causes permanent mental retardation through inability to digest phenylalanine
Treatment: a diet that is absent of any phenyalanine will result in a normal child-example of how environmental alteration can sometimes modify phenotype