Genetic disorders in children

Question 1

How many children in the UK are born with a genetic defect and by what percentage is hospital stay increased?

Answer 1

1 in 25

40%

Question 2

How might a child with genetic defects present?

Answer 2

Dysmorphic features
Multiple anomalies
Developmental delay/learning difficulties
A disease that recurs in the family

Question 3

List some dysmorphic features that might affect the hands and feet

Answer 3

Polydactyly

Rocker bottom feet

Question 4

What skin sign is often seen in genetic conditions?

Answer 4

Cafe au Lait spots

Question 5

What dysmorphic features may affect the face?

Answer 5

Low set ears
Down slanting eyes with prominent epicanthal folds
Micrognathia and or retrognathia

Question 6

By how much is the incidence of genetic disorders increased in consanguineous children

Answer 6

twice as high

Question 7

What are the causes of anomalies present at birth

Answer 7

Infections
Drugs (prescribed or illicit)
Birth/pregnancy complications
Genetic disorders

Question 8

What is Karyotype testing

Answer 8

Testing for chromosomal abnormalities, with a resolution of 30-40 genes

Question 9

What does FISH stand for

Answer 9

Fluorescent In-Situ Hybridisation

Question 10

What does QF-PCR stand for

Answer 10

Qualitative Fluorescent Polymerase Chain Reaction

Question 11

What is FISH used for

Answer 11

FISH is a targeted method that uses probes to specific regions of genes
Used for common aneuploidies

Question 12

What is QF-PCR used for

Answer 12

Amplifies specific regions of DNA, only used for common aneuplodies. It is rapid, specific and accurate

Question 13

What method is an example of microarray genetic testing

Answer 13

Comparative genomic hybridisation (CGH)

Question 14

What is the resolution of microarray testing

Answer 14

Single gene

Question 15

What does microarray testing do

Answer 15

Looks at the amount of material present (so cannot detect balanced translocations). Much more sensitive than karyotype, FISH or QF-PCR and detects 3x as many abnormalities

Question 16

What is next generation sequencing

Answer 16

Identifies the order of bases at a single base resolution

Question 17

What condition results from T21

Answer 17

Down syndrome

Question 18

What characteristics at birth can be identified in a down syndrome child

Answer 18

Hypotonic
Single palmar crease
Wide sandal gap (between 1st and second toe)
Down slanting eyes
Prominent epicanthal folds

Question 19

_____ is the commonest

genetic cause of learning difficulties

Answer 19

Down Syndrome

Question 20

Cardiac anomalies are present in __% of Down syndrome babies and the most common is ____

Answer 20

50%

Atrioventricular septal defect

Question 21

What condition is caused by an absent or partially absent X chromosome

Answer 21

Turner syndrome

Question 22

Turner Syndrome babies usually survive to birth (T/F)

Answer 22

False

Question 23

What are some clinical features of Turner Syndrome

Answer 23

Short Stature
Webbing of the neck 
Widely spaced nipples 
Congenital heart defects 
Infertility

Question 24

What is the most common heart defect in Turner syndrome children

Answer 24

Coarctation of the aorta

Question 25

What condition is caused by T18

Answer 25

Edwards Syndrome

Question 26

What condition is caused by T13

Answer 26

Patau syndrome

Question 27

Most children with Edwards Syndrome die in infancy (T/F)

Answer 27

True

Question 28

Most children with Patau syndrome die in infancy (T/F)

Answer 28

True

Question 29

What are some clinical signs of Edwards syndrome

Answer 29

``` Low birth weight Micrognathia Fixed overlapping fingers Rocker bottom feet Often cardiac and renal problems ```

Question 30

What are some clinical signs of Patau syndrome

Answer 30

Cleft lip and palate Polydactyly Small eyes Often abnormalities of the brain, heart and kidneys