Inheritance, MOA, Presentation of Genetic Diseases

Huntington's Disease: Inheritance

- Autosomal Dominant

Huntington's Disease: Presentation

- Causes nerve cells to break down over time → loss in coordination/muscle, cognitive decline with confusion/dementia

Marfan Syndrome: Inheritance

- Autosomal Dominant

Marfan Syndrome: MOA

- Nonfunctional fibrillin leads to changes in elastic fibers that are apart of connective tissue

Marfan syndrome: Presentation

- Tall/thin body build, curved spine, easily dislocated joints, dental issues, eye problems, heart/BV & lung problems

Achondroplasia: Inheritance

- Autosomal Dominant

Achondroplasia: MOA

- Mutations in growth factor receptor gene

Achondroplasia: Presentation

- Dwarfism with short extremities and normal sized heads, no change in life expectancy. Fatal if homozygous

Cystic Fibrosis: Inheritance

- Autosomal Recessive

Cystic Fibrosis: MOA

- Mutations in iron channel that helps regulate salt and water balance

- W/out salt movement, mucus in various organs becomes thick

Cystic Fibrosis: Presentation

- Difficulty breathing, frequent lung infections, poor digestion, chronic sinus infections, infertility

Tay-Sachs Disease: Inheritance

- Autosomal Recessive

Tay-Sachs Disease: MOA

- Enzyme that breaks down gangliosides is nonfunctional → they build up in nerve tissue → damage to brain and spinal cord

Tay-Sachs Disease: Presentation

- Muscle weakness, poor motor coordination, seizures, vision loss, speech problems

*Cherry red spot in macula*

Tay-Sachs Disease: More common in which group?

- People of Ashkenazi Jewish Descent

Xenoderma Pigmentosum: Inheritance

- Autosomal Revessive

Fragile X syndrome: Inheritance

- X-linked dominant

Fragile X syndrome: MOA

- Mutation of FMRP protein, an RNA binding protein involved in brain development

Fragile X syndrome: Presentation

- Males more severely affected, delayed cognitive function, autism, hyperactive, hand flapping, hyperextensible joints, large ears, elongated face, large testes

Vitamin D Resistant Rickets: Inheritance

- X-Linked Dominant

Vitamin D Resistant Rickets: MOA

- Mutation in Vitamin D receptor gene, leading to impaired low phosphate levels in the blood

Vitamin D Resistant Rickets: Presentation

- Bone deformities, bone pain, delayed growth, muscle weakness, dental abnormalities

Red-Green Color Blindness: Inheritance

- X-Linked Recessive

Red-Green Color Blindness: MOA

- Mutations that lead to the absence or malfunction of certain kinds of cones in the eye

Red-Green Color Blindness: Presentation

- Inability to distinguish shades of red and green, as well as their variations

Hemophilia A/B: Inheritance

- X-Linked Recessive

Hemophilia A/B: MOA

- Mutations in certain clotting factors

Hemophilia A/B: Presentation

- Excessive bleeding after surgery or dental procedures, easy bruising, blood in urine/stool, unexplained nosebleeds

Duchenne Muscular Dystrophy: Inheritance

- X-Linked Recessive

Duchenne Muscular Dystrophy: MOA

- Caused by mutations to dystrophin, a protein that helps stabilize muscle fibers during contraction and stretch

Duchenne Muscular Dystrophy: Presentation

- Muscle weakness, frequent falls, walking on toes, difficulty swallowing, scoliosis, weakened cardiac/respiratory muscles

Mitochondrial Myopathy: Inheritance

- Mitochondrial

Mitochondrial Myopathy: MOA

- Mutations in mitochondrial DNA → disruptions in mitochondrial function

Mitochondrial Myopathy: Presentation

- Muscle weakness, exercise intolerance, fatigue, lactic acidosis

*Red ragged fibers*