Genetics Flashcards
What is the role of paediatric genetics?
- Diagnosis in congenital malformations and learning disability
- Approach to dysmorphic child
- Investigation into developmental delay
What conditions is Down syndrome associated with?
- Learning disability
- Congenital heart disease
- Hypothyroidism
- Immunity
- Early onset Alzheimer disease
What ethical issues are there surrounding testing for Down syndrome?
- Regarded as standard care in Western world
- Non-invasive testing will soon be available
- Is a world without Down syndrome acceptable?
- Screening leads to termination
What does congenital mean?
- Present at birth
- Can be genetic, environmental or both
What are the causes of multiple congenital anomaly syndromes?
- 55% unknown
- 30% single gene disorders
- 10% chromosomal
- 5% teratogens
What is the epidemiology of congenital anomalies/
- 3% all births
- 20% children’s hospital admissions
- 30% infant deaths
Syndrome
A distinct group of symptoms and signs which associated together for a characteristic clinicl picture or entitiy
How common are multiple congenital anomalies?
- Individually rare
- Common as a group
How do you diagnose a rare intellectual disability or malformation syndrome?
- History
- Description
- Recognition of patterns
- Testing
What testing can be performed in diagnosis of a rare intellectual disability or malformation syndrome?
- Microarray standard
- Targeted testing
- Moving to exome and genome
What should be looked at when describing a dysmorphic child?
- Position and shape of facial features
- Hands
- Growth of child
- General features
What should be looked at regarding the head of a dysmorphic child?
- Shape
- Size: macrocephaly, microcephaly
- Ear position
What type of ears suggest lack of maturity?
Low-set, posteriorly rotated
What should be looked at regarding the eyes in a dysmorphic child?
Hypertelorism
-Inner canthal distance ICD and inter-pupillary distance IPD increased
Telecanthus / epicanthic folds
-ICD increased
What hand measurements should be taken when examining a dysmorphic child?
- Finger length
- Digital abnormalities
- Palmar creases