Genetic conditions Flashcards
(50 cards)
What is Klinefelter syndrome
When a male has an additional X chromosome making them 47 XXY
Give 5 clinical features of Klinefelter syndrome
- Taller height
- Infertility
- Gynaecomastia (swelling)
- Small testes
- Subtle learning difficulties - speech and language
How is Klinefelter syndrome managed
- testosterone injections
- Breast reduction surgery
- advanced IVF techniques to allow fertility
Give 3 complications of Klinefelter syndrome
- diabetes
- breast cancer
- osteoporosis
What is turners syndrome
chromosomal disorder involving a complete or partial absence of the second X chromosome in females making them 45 XO
Give 6 clinical features of turners syndrome
- short stature
- neck webbing
- widely spaced nipples
- lymphoedema in neonates
- delayed/ incomplete puberty (primary amenorrhoea)
- underdeveloped ovaries with reduced function (infertility)
Give 4 conditions associated with turners syndrome
- bicuspid aortic valve
- coarctation of the aorta
- hypothyroidism
- aortic dissection and dilation
How is turners syndrome managed
- Growth hormone therapy
- Oestrogen replacement can help establish female secondary sex characteristics
- Monitoring for associated conditions
What is the main inheritance pattern of Noonan syndrome
Autosomal dominant
Give 6 features of Noonan syndrome
- Short stature
- wide-spaced down-slanting eyes
- webbed neck
- low-set posteriorly rotated ears
- pectus excavatum
- wide-spaced nipples
Give 4 conditions associated with Noonan syndrome
- Congenital heart disease
- Cryptorchidism (undescended testes)
- bleeding disorders (factor XI deficicency)
- learning difficulties
What 3 congenital heart conditions are common in children with Noonan syndrome
- Hypertrophic cardiomyopathy
- atrial septal defect
- pulmonary valve stenosis
How is Noonan syndrome managed
- supportive management with MDT
- corrective heart surgery is often needed for congenital HD
What causes fragile X syndrome
trinucleotide repeat disorder on the X chromosome
Inheritance pattern of fragile X syndrome
X linked but unclear whether it is dominant or recessive
- females are affected variably
Give 5 features of fragile X syndrome
- Large testicles after puberty
- Long, narrow face
- large posteriorly everted ears
- moderate-severe learning difficulties
- hypermobile joints
- mitral valve prolapse
What is Prader-Willi syndrome
A genetic condition caused by the absence of the active prader-willi gene on the long arm of chromosome 15
Prader-Willi syndrome typically occurs due to one of two main genetic mutations. State these in relation to PWS
- Paternal deletion of involved genes (mc)
- maternal uniparental disomy - two copies of chromosome 15 inherited from mother
Give 5 clinical features of Prader-Willi syndrome
- Constant insatiable hunger leading to obesity (starting in older child)
- central hypotonia
- Neonatal feeding difficulties
- hypogonadism
- developmental delay and learning difficulties
Give 2 symptoms associated with hypotonia in neonates with PWS
- weak cry
- poor suck
Give 4 physical features that may be seen in a person with PWS
- almond-shaped face
- narrow forehead
- Thin upper lip
- small hands and feet, short stature
How is Prader-Willi syndrome managed
MDT management: dietician, endocrinologists, physios, psychiatrist
* management of access to food - locks on fridge/ cupboards
* Growth hormone treatment in first year of life - improve muscle development and body composition
What is Angelman syndrome
genetic condition caused by a mutation or deletion in the UBE3A gene on chromosome 15
Angelman syndrome typically occurs due to one of two main genetic mutations. State these relative to Angelman
- deletion of UBE3A gene from maternal chromosome 15 (mc)
- uniparental disomy - person inherits two copies of chromosome 15 from father (no maternal copies)
