Genetics Flashcards
Behcet’s Syndrome
Associated HLA
HLA 51
Osteogenesis Imperfecta
Associated collagen defect
Type 1 collagen
Oncogenes
- Normal function
- Abnormal function
- Examples (2)
Normal = promote signal pathways of cell growth
Abnormal = dominates, loss of growth control
e.g. RAS - G protein
e.g. c-myc - transcription factor
- Associated with Burkitt’s lymphoma
C-myc
- Type of gene
- Association
= oncogene
Burkitt’s Lymphoma
RAS
- Type of gene
= oncogene
Tumour suppressor genes
- Normal function
- Abnormal function
- Examples (2)
Normal = inhibit the cell cycle
Abnormal = loss of function, loss of growth control
e.g. p53
e.g. Rb gene
- Associated with retinoblastoma
Rb
- Type of gene
- Association
= tumour suppressor gene
Retinoblastoma
p53
- Type of gene
- Function
- Association
= tumour suppressor gene
Regulates apoptosis
Li-Fraumeni
Trisomy 21
- Most common cause
- Cardiac presentations (3)
Maternal non-dysjunction
- ASD (failure of fusion of inferior and superior cardiac cushions)
- PDA
- Tetralogy of Fallot
Patau’s Syndrome
Trisomy 13
Edward’s Syndrome
Trisomy 18
Abnormality in CML
Philadelphia Chromosome
9:22 translocation
9:22 translocation
= Philadelphia chromosome
CML
APC
- Type of gene
- Location
= tumour suppressor gene
- Chromosome 5
- Familial adenomatous polyposis
Lynch Syndrome
- Genetic problem
- Inheritance
= DNA mismatch repair
- Autosomal dominant
Inheritance - Tuberous Sclerosis
A dominant
Inheritance - hereditary spherocytosis
A dominant
Inheritance - Charcot Marie Tooth (HSMN)
A dominant
Inheritance - Myotonic dystrophy
- Abnormality
A dominant
- Protein kinase trinucleotide repeat
Inheritance - achondroplasia
- Abnormality
A dominant
- fibroblast 3 mutation
Inheritance - cystic fibrosis
- Abnormality
A recessive
deletion mutation
Inheritance - inborn errors of metabolism
Examples (5)
A recessive
Gaucher disease
PKU
Tay Sach’s
Homocystinuria
Glycogen storage disease
Genetic abnormality in Huntington’s Disease
- Chromosome
Trinucelotide repeat
Chromosome 4
Genetic abnormality in Frederich’s Ataxia
- Inheritance
- Chromosome
Trinucelotide repeat
Autosomal recessive
Chromosome 9
Trinucelotide repeat disorders
- What do they demonstrate?
- Effect of age?
Genetic anticipation = presents at earlier age with each generation
Repeats expand with age = somatic instability
Inheritance - G6PD deficiency
X linked recessive
Inheritance - Duchenne and Becker Muscular Dystrophy
- Mutation type
- Severity
X linked recessive
Duchenne = nonsense mutation, more severe
Becker = in frame mutation, less severe
MHC
- What is it?
- Where is it found?
Major histocompatibility complex
- Chromosome 6
Class I MHC
- Where found?
- Subclasses?
- Immune response cell?
All nucleated cells
HLA-A, HLA-B, HLA C - get one each from each parent
CD8+ T cells respond - involved in ACUTE rejection
Class II MHC
- Where found (3)?
- Subclasses?
- Immune response cell?
Dendritic cells, B cells, monophagocytes
DR2, DR3, DR4
CD4+ T cells
HLA3
Haemochromatosis
Haemochromatosis
HLA-A3
HLA B51
Behcet’s Disease
Behcet’s Disease
HLA B51
HLAB27 (4)
Ankylosing spondylitis
Psoriatic arthritis
Reiter’s syndrome
Anterior uveitis
HLA DR2
Multiple sclerosis
Multiple sclerosis
HLA DR2
HLA DR3 (6)
Dermatitis herpetiformis/coeliac disease
T1DM
Grave’s Disase
SLE
PBC
Myaesthenia gravis
Dermatitis Herpetiformis
HLA DR3
Acute transplant rejection
- Immune cell in control
- How occurs
T cell mediated
- dendritic cells found in transplant migrate to local lymph nodes and activate T cells
T1DM
HLA DR3
HLA DR4
Rheumatoid Arthritis
HLA DR4
- Specifically DRB1
Hyperacute rejection
- Immune cell in control
- How occurs
B cell mediated
- Antibodies formed due to previous sensitisation BIND to endothelium
- Destruction of implant
Genetic mutation associated with prostate cancer
BRAC2
(also BRAC1 but not as much)
Mode of inheritance - frederich’s ataxia
Autosomal recessive
Frederichs ataxia is excessive (recessive)
Association with Oropharyngeal cancer
HPV 16/18
Which part of the cell cycle determines the length?
G1 - cell spends most of its time here: prepares for DNA replication
Translocation associated with follicular lymphoma
14:18
Translocation asscoiated with AMPL
15:17
Collagen mutation in Ehler’s Danlos
Collagen Type 3
E and 3 are mirror image
Ataxic Telangiectasia - gene implicated
ATM gene
Technique used for DNA sequencing?
Southern Blotting
