Genetics and Metabolism

1.    Genetics.

***) All of the following are inherited as autosomal dominant, except:

A.    Neurofibromatosis

B.     Tuberous sclerosis

C.     Achondroplasia

D.    Cystic fibrosis

E.     Adult type polycystic kidney disease

Answer: D* Cystic fibrosis

***) In autosomal dominant inheritance the trait will be found in one parent and:

A.    25% of daughters and 75% of sons

B.     75% of daughters and 25% of sons

C.     50% of sons and 50% of daughters

D.    Only daughters

E.     Only sons

Answer: C* 50% of sons and 50% of daughters

***) In autosomal dominant inheritance, the chance of having affected offspring in each pregnancy is:

A.    25%

B.     50%

C.     75%

D.    100%

E.     Only male

Answer: B* 50%

2.    Genetic Syndromes.

***) Chromosomal study is indicated in all of the following, except:

A.    Down syndrome

B.     Meningomyelocele and hydrocephalus

C.     Recurrent abortion loss

D.    Turner syndrome

E.     Ambiguous genitalia

Answer: B* Meningomyelocele and hydrocephalus

***) The most likely reason for the extra chromosome in Down's syndrome is:

A.    Anaphase lag

B.     Translocation

C.     No disjunction

D.    Oogenesis

E.     Fragmentation

Answer: C* No disjunction

***) All of the following are features of trisomy 21 (Down), except:

A.    Hypotonia

B.     Microcephaly

C.     Clinodactyly

D.    Recurrent chest infections

E.     Normal development

Answer: E* Normal development

***) Clinical features of Down's syndrome include all of the following, except:

A.    Mental retardation

B.     Microcephaly with flattening of occiput

C.     Muscle hypertonia

D.    Short and incurve little finger

E.     Simian crease

Answer: C* Muscle hypertonia

***) All the following are findings in Trisomy 21 except:

A.    Learning difficulties

B.     Protruding tongue

C.     Congenital heart defects

D.    Single transverse palmar crease

E.     Hypertonia

Answer: E* Hypertonia

***) A cardiac disorder commonly associated with Turner's syndrome is:

A.    Mitral stenosis

B.     Coarctation of aorta

C.     Pulmonary stenosis

D.    Tetralogy of Fallot

E.     Absence of pulmonary valves

Answer: B* Coarctation of aorta

3.    Metabolic Disease.

***) Regarding acrodermatitis enteropathica all are true, except:

A.    Chronic diarrhea is present

B.     Caused by zinc deficiency

C.     Perioral dermatitis

D.    Loss of hair

E.     Associated with multiple congenital anomalies

Answer: E* Associated with multiple congenital anomalies

***) All of the following metabolic disorders are treated by a specifically modified formula and or diet, except:

A.    Phenylketonuria

B.     Maple syrup urine disease

C.     Galactosemia

D.    Cystinosis

E.     Fructosemia

Answer: D* Cystinosis

4.    Phenylketonuria (PKU).

***) All are recognized findings in Phenylketonuria PKU, except:

A.    Seizures

B.     Macrocephaly

C.     Eczema

D.    Blond hair and blue sclera

E.     Failure to thrive

Answer: E* Failure to thrive