Russell-Silver Syndrome

Question 1

What are the symptoms of Russell-Silver Syndrome?

Answer 1

Intrauterine growth restriction
Low birth weight
Short stature (children and adults)
Relatively macrocephaly
Craniofacial abnormalities
Asymmetrical limbs
Feeding difficulties 
GERD

Question 2

What genes are involved in Russell-Silver syndrome?

Answer 2

Chromosome 11
Loss of methylation at 11p15.1 (Gene: H19 and IGF2)

Chromosome 7
Maternal uniparental disomy (both copies of chromosome 7 come from the mother)

Question 3

What is the inheritance pattern of Russell-Silver Syndrome?

Answer 3

Most cases are not inherited {spontaneous mutations}

Depending on family–> pattern of inheritance within certain families vary

Some families–> autosomal dominant

Some families–> autosomal recessive

Question 4

For those who are autosomal dominant, is the homozygous dominant is lethal?

Answer 4

It has not been shown to be lethal

Question 5

What is the phenotype of the heterozygous for Russell-Silver Syndrome (autosomal recessive inheritance pattern)?

Answer 5

Heterozygous phenotype have shown no symptoms