Genetics Flashcards
What are the features, testing and management involved in Down’s Syndrome?
Trisomy 21
Hypotonia, brachycephaly (small head/ flat back), short neck, short stature, flat face/nose, prominent eyelid folds, Upward palpebral tissues (between eyelids), single planar crease
Screening
Antenatal
1. Combined test- 11-12 weeks- 1st line- USS and Maternal blood- beta-HCG (will be higher) and PAPPA (will be lower)
2.Triple test 14-20 wks
Beta- HCG (higher), AFPand serum estriol (both lower)
3.Quadruple test 14-20 wks
All of triple and inhibit A (high)
Antenatal testing
CVS- before 15 weeks
Amniocentesis after this
or NIPT
Management
MDT
Social care and benefits
Educational support
Regular thyroid checks
Echos
Regular audiometry and eye checks
Life expectancy 60
Complications
Learning disability
Recurrent otitis media
Deafness
Visual problems- myopia, strabismus, cataracts
Hypothyroid
Cardiac issues (ASD,VSD, PDA, tetralogy)
Atlantoaxial instability
AML
Dementia
What are the features and management of Kleinfleter’s syndrome
Felt HER- an extra X
Male has an additional X chromosome
47 XXY/ 48 XXXY/ 49 XXXXXY
Features at puberty
Taller
Wider hips
Gynaecomastia
Weaker muscles
Small testicles
Reduced libido
Shy
Infertile
Subtle learning difficulty
Investigations
High LH and FSH
Low testosterone
Management
Testosterone injections
Advanced IVF for fertility
Breast reduction surgery
MDT input
What are the features of Turner syndrome
Turn and say bye “XO”
Female has one single X chromosome 45XO
Triad
Short stature, webbed neck, Wide spaced nipples
high arching palate, downward sloping eyes with ptosis, , cubits valgus (abnormal elbow), late puberty, underdeveloped ovaries- infertility
Management
Growth hormone
Oestrogen and progesterone
Fertility treatment
Associated conditions
Otitis media
Recurrent UTI
Coarctation aorta
Hypothyroid
HTN
Obesity
Diabetes
Oesteoporosis
Leaning disability
Horse shoe kidney
What are the features and management of Noonan Syndrome?
Autosomal dominant
Stenosis is for old people- NAN
Short, broad forehead, down sloping eyes (ptosis), wide space between eyes, prominent nasolabial folds, low set ears, webbed neck, wide space nipples, wispy hair
Associated with
Pulmonary valve stenosis (ejection systolic murmur), hypertrophic cardiomyopathy, ASD
Undescended testes in boys
Learning disability
Bleeding disorders
Lymphoedema
Increased risk of leukaemia and neuroblastoma
Management
MDT
Manage congenital HD
What are the features of Marfan’s syndrome
Autosomal dominant- affects gene for fibrillin
Tall, long neck and limbs, fingers, high arch palate, hyper mobility, pacts carinatum/ excavated
Murmur of mitral or aortic regurgitation
Associated with
Lens dislocation in eye
Join dislocation
Scoliosis
Pneumothorax
GORD
Mitral/Aortic valve prolapse (with regurg)
Aortic aneurysms
Management
Minimise blood pressure and HR - avoid intense exercise/ caffeine
Give B-Blockers and ARBS
Careful in pregnancy - increases risk of aortic aneurysms
Echos and ophthalmology review
What are the features and management of fragile X syndrome
X-linked- don’t know if dominant or recessive
Males always affected- females sometimes
FMR1 gene mutation
Fragile= a feeling= more related to behaviour
Not fragile- big balls , big head
Delayed speech and language development
Intellectual disability
Long narrow face
Large ears
Large testicles after puberty
Hypermobile joints
ADHD
Autism
Seizures
Management
Supportive
What are the features and management of Prader Willi syndrome
Loss of function in gene 15 inherited from father/ both copies of chromosome 15 come from mum
Insatiable hunger- obesity
Poor muscle tone as a baby
Mild-moderate learning disability
Hypogonadism (no sex hormones)
Fair, soft skin, prone to bruise
Anxiety
Narrow forehead
Almond eyes
Strabismus (squint)
Thin upper lip
Downturned mouth
Management
Growth hormone to improve muscle development and body composition
Dietician
What are the features and management of Angelman syndrome
Loss of UBE3A gene- Chromosome 15
Features
Wee angel- very happy
Obsessed with water
Wide spaced teeth
Delay/absence of speech
Atacia
Laughter
Hand flapping
Abnormal sleep
Epilepsy
ADHD
Microcephaly
Fair light skin with blue eyes- look like an angel
Management
MDT
What are the features and management of William Syndrome
Chromosome 7 deletion - random - not inherited
Prince William is a social star
Starburst eyes- star pattern on iris
Very social personality, big smile
Broad forehead
Flatted nasal bridge
Small chin
Mild learning disability
Long philtre (between upper and lower lip)
Associations
Supravalvular aortic stenosis (prince william is better- super)
HTN
Hypercalcaemia
ADHD
Management
MDT
Echos and BP
Low calcium diet
What are the features and management of Edwards syndrome
Trisomy 18
Quadruple testing will show
Low AFP, Low estriol, Low BHCG and normal inhibin A
Prince Edward is low in the order of monarchy- all findings low
Features
Low set ears
Rocker bottom feet
Overlapping fingers
Small jaw
What are the features of Patau syndrome
Trisomy 13
Cleft palate/ lip
P for Patau and palate
Skinny can’t gain weight
Extra fingers/ toes
Low set ears
Hypotonia
Small head and jaw
Close together eyes
What are the features of Kartagener’s syndrome
Primary ciliary dyskinesia
Associated with dextocardia - quiet heart sounds and small complexes in lateral ECG leads
Bronchiectasis
Recurrent sinusitis
Subfertility (sperm are not mobile, no cilia in fallopian tube)
What are the features of tuberous sclerosis
Autosomal dominant
Cutaneous features
ash leaf spots- whiter skin spots
rough skin over lumbar spine (shagreen patch)
Butterfly angiofibromas over nose
Cafe au lit spots
Fibromata under nails
Developmental delay
Epilepsy
Associations
Rhabdomyomas of heart
Polycystic kidneys
Gliomas in brain lesions
Lung cysts
White areas on the retina
