Autosomal Dominant Inheritance

By: Jack Wernet

Autosomal Dominance “A gene on one of the non-sex chromosomes

that is always expressed, even if only one copy is present.” (Human Genome Project Information at the U.S. Department of Energy)

“Autosomal”“The gene in question is locatedon one of the numbered, or non-sex, chromosomes”

“Dominance”“A single copy of the disease associated mutation is enough to cause the disease.”

Chance of Dominance

Hybrid reproduction with the recessive gene results in a 50% chance for disease in the offspring.

A full list of genotypes and phenotypes

Keeps track of genetic diseases

Brachydactyly

OMIM – 112500 Autosomal Dominant Discovered in 1903 by William Curtis

Farabee This was the 1st record of this disease. In 1951 it was classified as type A1

Brachydactyly Treatment for this disease is not

needed

Effects

Born with the disease Short Fingers and Toes Normal lives There are many different forms of

Brachydactyly.

Huntington Disease (HD) OMIM – 143100 The gene was discovered in 1933 by many

researchers. Usually appears around the ages 40-50 (live about

15 yrs after signs) Excess CAG triplet mutation in HTT Protein Loss of Neurons Nothing to cure or stop this disease Goal of any treatment is to slow the process of the

destruction of these neurons“Symptoms include: poor memory, depression and/or mood swings, lack of coordination, twitching or other uncontrolled

movements, and difficulty walking, speaking, and/or swallowing. In the late stages of the disease, a person will need help doing even simple tasks, such as getting dressed.” (The University of

Utah)

Huntingtin (HTT) Protein In all cells of the body Selectively kills nerve cells HD patients affect a group of nerve cells at

the base of the brain called basal ganglia. It controls the muscle driven movements of

the body. HD Basal Ganglia

is smaller, affecting these movements

Neurofibromatosis (NF)

OMIM – 162200 Can be passed down to children Can also occur by a genetic mutation Affects how nerve cells form and grow. Forms small benign tumors –

neurofibromas No cure yet, but tumor can be surgically

removed. Also symptoms can be treated. 2 major types:

NF1 NF2

NF1

“Causes skin changes and deformed bones and usually starts at birth.” (Medline Plus)

This type is present at birth

NF2

“Causes hearing loss, ringing in the ears and poor balance. It often starts in the teen years.” (Medline Plus)

Usually begins in a teenager.

Marfan Syndrome

OMIM – 154700 First described and named after Antoine Marfan in 1896 Causes defects in the

protein Fibrillin No cure yet, but all

symptoms can be treated.

Fibrillin

A protein that is a part of the connective tissue in the body.

A defect in Fibrillin causes a defect in the connective tissue.

Causes extremely long arms, fingers, a very tall body structure, and loose joints. Symptoms include: spider like

fingers, flat feet, learning disabilities, flexible joints,

small lower jaw, and a chest that sinks in or out.

Alzheimer Disease

1% of all cases of Alzheimer is inherited

Usually occurs over the age of 65 Caused by a mutation in the APP

gene There is no cure or treatment to slow

down the process of Alzheimer Symptoms can be treated

This disease can result in frequent memory loss, mood swings, loss of

confidence and difficulty performing everyday activities.

APP Gene

Creates amyloid precursor proteins Mutation in the gene results in a

mutation in the protein. This creates an excess amount of

amyloid β peptide which causes Alzheimer disease.

Quiz pt. 1

Huntington disease usually appears around age:a. at birthb. 10-20c. 40-50d. 65

Quiz pt. 1

Huntington disease usually appears around age:a. at birthb. 10-20c. 40-50d. 65

Quiz pt. 2

A mutation in the APP gene causes what disease?a. Alzheimer Diseaseb. Huntington Diseasec. Neurofibromatosisd. Brachydactyly

Quiz pt. 2

A mutation in the APP gene causes what disease?a. Alzheimer Diseaseb. Huntington Diseasec. Neurofibromatosisd. Brachydactyly