Single Gene Disorders and Complex Inheritance Flashcards
What type of disorder is Marfan syndrome?
Disorder of connective tissues
Where is the mutation in Marfan syndrome?
Chromosome 15- fibrillin I gene
What are life threatening components of Marfan’s syndrome?
Cardiovascular lesions- aorta and valves
What do individuals with Marfan’s syndrome look like?
Tall, slender, long appendages
Arachnodactyl (spider fingers)
Where is the mutation in Huntington disease?
Chromosome 4 has abnormal number of CAG repeats
What are signs of Huntington Disease?
Mental deterioration, involuntary appendage movement
Late acting lethal dominant
In the most common form of albinisms, what is there a lack of?
Tyrosinase
What are some things associated with albinism?
Risk of sunburn
Skin cancer
impaired vision
photosensitivity
What are symptoms of phenylketonuria?
Irritabile, tremorous, slow developing retardation
affects nervous system
Where does the excess phenylalanine diet show up?
Urine (musty odor)
What is defective in cystic fibrosis?
chloride ion membrane transporter
What is the most common single-gene disorder in Caucasians?
Cystic fibrosis
Where is the mutation found in cystic fibrosis?
Chromosome 7
What is hemophilia A due to?
Lack of Factor VIII
What does a person with triplet repeat mutations (Fragile X) have?
CGG repeats; 230-400 repeats
What amplifies the triplet repeat mutations (Fragile X syndrome)?
Oogensis
How is mitochondrial genes passed?
Through the mother
What do mitochondrial gene mutations code for?
Oxidative respiration enzymes
What is Prader-Willi syndrome caused by?
Deletion on paternal 15
What is Angelman Syndrome caused by?
Deletion on maternal 15
In which syndrome do individuals laugh inappropriately?
Angelman Syndrome
What disorders are where there are two or more mutant genes?
Polygenic disorders
What is required for digenic retinitis pigmentosa?
2 rare mutations in 2 different unlinked genes which are part of the photoreceptor
What are the three factors required for idiopathic cerebral vein thrombosis?
2 genetic (Missense mutation in clotting factor V, variation in 3' UTR of prothombin gene) 1 environmental (oral contraceptives)
