Genetics Flashcards
Adult Polycystic Kidney Disease mode of inheritance?
Autosomal Dominant
Adult Polycystic Kidney Disease happens on which gene and which chromosome
PKD1
Chromosome 16
Prader Willi happens through which gene?
Paternal 15Q
Angelman Syndrome happens through which gene
Maternal 15q
What is Mendelian Inheritance?
Single gene disease on non sex chormosomes
How many copies of an affected gene do you need to have to have an Autosomal Dominant condition?
Single copy of diseased gene
How many copies of an affected gene do you need to have to have an autosomal recessive condition?
Two copies of disease gene
How many copies of an affected gene do you need to be a carrier of an autosomal recessive condition?
One copy of diseased gene
In autosomal recessive condition where both parents have 1 copy of diseased gene what is the chance of a child being affected by the disease?
1 in 4 (25%)
In autosomal recessive condition where both parents have 1 copy of diseased gene what is the chance of a child being a carrier of disease?
2 in 4 (1 Abnormal, 1 Normal)
In autosomal recessive condition where both parents have 1 copy of diseased gene what is the chance of a child being not affected by disease?
1 in 4 (25%)
In autosomal dominant condition what is the chance of a child having the disease where 1 parent has disease and 1 parent does not?
2 in 4 (50%)
In autosomal dominant condition what is the chance of a child not having the disease where 1 parent has disease and 1 parent does not?
2 in 4 (50%
Autosomal Recessive
- Both parents unaffected
- 1 Sibling has condition
- 1 sibling does not have condition
Chance of sibling that does not have condition being carrier?
2 in 3
Because both parents will be carriers and the child does not have the condition which leaves three options that could be possible
Name the cause of Angelman Syndrome (2)
Loss of function of UBE3A Gene
Deletion on Chromosome 15
Name common feautres of Angelman Syndrome? (7)
Delayed Development and LD
Speech Issues
Fascination with water
Happy demeanor
Wide spaced teeth
Inappropriate laughter
Hand flapping
Cause of Angelman Syndrome (2)
Loss of function of UBE3A Gene
and Deletion on Chromosome 15
Name 8 autosomal dominant conditions
- Achondroplasia
- Adult Polycystic Kidney Disease
- Familal Alzheimers Disease
- Familial Hypercholesterolaemia
- Huntingtons Chorea
- Marfan Syndrome
- Neurofibromatosis Type I
- Von Willebrand Disease
Name 8 autosomal dominant conditions
- Achondroplasia
- Adult Polycystic Kidney Disease
- Familal Alzheimers Disease
- Familial Hypercholesterolaemia
- Huntingtons Chorea
- Marfan Syndrome
- Neurofibromatosis Type I
- Von Willebrand Disease
Name 5 common autosomal recessive haematology conditions?
Haemochromatosis
Phenylketonuria
Sickle Cell
Haemophilia A
Haemophilia B
Name a common paediatric msk autosomal recessive condition?
Duchenne Muscular Dystrophy
Name a common autosomal recessive respiratory condition?
Cystic Fibrosis
name a common autosomal recessive gi condition?
Wilsons Disease
What does Homozygous mean?
Both gene copies abnormal
What does Heterozygous mean?
One gene copy abnormal
How many pairs of chromosomes does an individual have?
23 (46 in total)
How many sex chromosomes does have a female have?
Two X
How many sex chromosomes does a male have?
One X and One Y
What is the chromosome abnormality in Myeloid Leukaemia?
Translocation of philadelphia chromosome (9:22)
What is the chromosome abnormality in Acute Promyelotic Leukaemia?
15:17
Which gene causes Familial Adenomatous Polyposis?
APC Gene
which gene causes Hereditary Retinoblastoma?
RB gene
Cri Du Chat is what type of genetic condition?
Deletion disorder missing chromosome 5
Charcot Marie Tooth is what type of genetic condition?
Duplication disorder on chromosome 17
How does Charcot marie tooth present? (3)
Sensory Neuropathy
Motor Neuropathy
Pes Cavus (High Arch Foot)
Patau is what trisome condition?
Trisomy 13
Edwards is what Trisome condition?
Trisomy 18
Downs is what trisome condition?
Trisomy 21
How does Downs Syndrome typically present? (8)
Hypotonia
Brachycephaly
Short Neck
Short Height
Flat Face/Nose
Prominent Epicanthic Folds (Eyes)
Upward Sloping Palpebral Fissures
Single Palmar Crease
What is Brachycephaly?
Small Head/Flat Back
Where can prominent epicanthic folds be found?
Eyes
Name complications of Downs Syndrome? (7)
Learning Difficult
Recurrent Otitis Media due to Eustachian tuBE ISSUES
Visual Issues
Hypothyrodism
ASD/VSD Cardiac
Leukaemia
Dementia
First line diagnostic test for Downs? at what week?
Combined Test (Ultrasound and Maternal Bloods: Beta HCG and PAPPA) at 11-14 Weeks
What will Beta HCG and PAPPA tested at 11-14 weeks in downs show?
Increased Beta HCG
Decreased PAPPA
What test to measure neck in Downs?
Nuchal Transluency ?6mm
What does the Triple Test in Downs at 14-20 weeks look at?
High Beta HCG
Low Alpha Fetoprotein
Low Serum Oestriol
Quadruple Test at 14-20 weeks in Downs what does that look at?
Inhibin A
What is Fragile X Syndrome?
Mutation in Fragile X Mental Retardation 1 Gene (FRM1) on X Chromosome
Symptoms of Fragile X Syndrome? (8)
Intellectual Disability
Long Narrow Face
Large Ears
Large Testicles after puberty
Hypermobile Joints
ADHD
Seizures
Autism
Testing for BRCA1 and Huntingtons is what type of genetic test?
Predictive
Huntingtons Disease has what type of mutation?
CAG Expression
Kleinfelter’s Syndrome affects what gender?
Male
Kleinfelter’s Syndrome is what kind of condition?
Additional X Chromosome in Males (47 xxy)
Features of Kleinfelter’s Syndrome (8)
Tall
Wide Hips
Gynaecomastia
Weak Muscles
Small Testicles
Reduced Libido
Infertiluty
Subtle LD
Treatment for Kleinfelter’s Syndrome? (2)
Testosterone Injections
Breast Reduction Surgery
How is Marfans Inherited?
Autosomal Dominant
What is Marfans
affects gene responsible for creating fibrillin which affects connective tissue
Features of Marfans? (8)
Tall
Long Neck
Long Arms/Legs
Long Fingers
High Arch Palate
Hypermobility
Chest wall deformity
Downward slope palpabrle fissures
Associations with Marfans? (7)
Lens Dislocation
Joint Dislocation
Scoliosis
Pneumothorax
GOR
Mitral Valve/Aortic Valve Prolapse with Regurg
Aortic Aneurysm
Duchenne Muscular Dystrophy is what type of condition?
X Linked
Neurofibromatosis Type 1 is what type of condition?
Autosomal Dominant on 17Q Gene
Features of Neurofibromatosis Type 2? (3)
Bilateral Acoustic Neuromas
CNS and Spinal Tumours
Cafe Au Lait Spots
Myotonic Dystrophy is inherited how? (2)
Autosomal Dominant
CTG Repeat
Noonans is inherited how?
Autosomal Dominant
Features of Noonans (9)
Short
Broad Forehead
Slope Eyes with Ptosis
Hyperterolism (wide space between eyes)
Prom Nasolabial Folds
Low Set Ears
Wide Nipples
Webbed Neck
Pul Valve Stenosis
What is Prader Willi Syndrome
Loss of functional genes on proximal arm of chromosome 15 inherited from father
Features of Prader Willi Syndrome? (9)
- Constant insatiable hunger > Obesity
- Hypotonia
- Mild-Moderate LD
- Hypogonadism
- Dysmorphic Features
- Narrow Forehead
- Almond shaped eyes
- Strabismus
Thin upper lip
Lynch Syndrome increases risk of what two types of cancer in particular?
Endometrial and Colon
Name four common trinucleotide repeat disorders?
Fragile X (CGG)
Huntingtons (CAG)
Myotonic Dystrophy (CTG)
Frederich Ataxia (GAA)
Tuberous Sclerosis presents with what triad?
Epilepsy, Learning Difficulty, Skin Lesions (Harmatomas)
How is Tuberous Sclerosis inherited?
Autosomal Dominant
How is Turners Inherited?
Single X Chromosome 45
Features of Turners? (8)
Short
Webbed Neck
High Arch Palate
Downward Slope Eyes with Ptosis
Broad Chest/Wide Spaced Nipples
Cubitus Valgus (Abnormal Elbow Angle)
Underdeveloped Ovaries
Late/Incomplete Puberty
