e. 5%

c. 35%

b. 20%

d. 90%

a. 70%

c. Children with Down syndrome have characteristic facies and habitus

a. It is the most common genetic cause of learning disability

e. IQ in adults is usually less than 50

d. Learning disability is evident before the age of 1 year

b. It is due to trisomy of chromosome 21

c. Children with Down syndrome have characteristic facies and habitus

It is due to trisomy of chromosome 17

IQ is usually normal

It is caused only by non-disjunction of chromosomes during meiosis

Children with the syndrome have normal genitalia

Children with the syndrome may have rocker-bottom feet

Incidence per 1000 live births increases for women over 35

The usual genetic cause is a Robertsonian translocation

Raised IgM and IgG levels are features

Most children with Down syndrome are born to mothers under the age of 35

About half of people with Down syndrome have congenital heart defects

Hypothyroidism

Diabetes

Syphilis

Measles

German measles

Vascular dementia

Hyperthyroidism

Hypermetropia

Depression

Macrocephaly

Protruding tongue

High-arched palate

Short stature

Simian crease

Kayser–Fleischer ring

Klinefelter syndrome

Turner syndrome

Trisomy X

XYY male

Down syndrome

Mild to moderate learning disability

Obesity

Acromicria

Tall stature

Hypogenitalism

Normal IQ

Paroxysms of crying

Micrognathia

Epilepsy

Macrocephaly

Absence of a mental illness

Deficit in at least one area of adaptive functioning

IQ below 60

Onset before age 18 years

Onset before age 12 years