Genetic Disease

Question 1

Single- gene disorder: cystic fibrosis

Answer 1

Signs and symptoms - sinus problems, nose growths, excessive mucus, trouble breathing, frequent lung infections, enlarged heart

genetics- autosomal recessive disorder, faulty 7p31 gene

physiology - gene codes for chlorine channel

Question 2

How mutations within different genes cause different neuromuscular disorders

Answer 2

myotonic dystrophy - autosomal dominant disorder, severe distal muscle weakness and learning disabilities, age of onset decreases with successive generations

Duchenne muscular dystrophy - X-linked recessive inheritance, results from mutation of dystrophin gene, weakness of proximal muscles, delay in walking, death around 20

Question 3

basic mechanisms of inherited genetic disposition to cancer

Answer 3

Proto-oncogenes - code for cell growth and regulation, mutations turn them into oncogenes which do not regulate cell growth forming tumour

Tumour-suppresor genes - act as brakes for cell growth, inhibit cell cycle, cancer arises when both copies of a gene fails