Paediatric Genetics

Question 1

What are the major mechanisms of congenital malformations?

Answer 1

Congenital meansPresent at birth
Can be due to: Genetic or environmental, Or both

Multiple congenital anomaly syndromes: 
30% single gene disorders
10% chromosomal
5% teratogens 
55% unknown

Malformations, sequence (eg one abnormality leads to another), deformation & disruption, association (eg two or more features occur together more often than expected by chance, mechanism unclear, like VATER), syndrome (eg distinct group of symptoms and signs which associated together form a characteristic clinical picture or entity)

Question 2

How would you assess dysmorphic syndromes and learning disabilities and what role does genomics play in this?

Answer 2

Depends on clinical experience 
Gestalt (instant recognition)
And also learn to recognise pattern of features
Use of databases 
Genomic analysis

Question 3

How would you approach the diagnosis of patients with complex malformations?

Answer 3

History
Description: position and shape of facial features, hands (finger length, digital abnormalities, palmar creases), growth, general features, head (shape, size, ear position), eyes
Recognition of patterns
Testing:
- standard: biochemical, chromosome structure, microarray is now standard
- targeted
Moving towards exome/genome

Question 4

What are some key paediatric genetic conditions?

Answer 4

Turner syndrome
22q11 deletion
Down syndrome