1. OSCE PEDIATRICS
GENETICS
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2. Spot 1
 Identify the pattern of inheritance
 Name 3 conditions with similar inheritance
 What is the degree of inheritance?
 Which sex is affected ?
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3.  Autosomal dominant
 NF1 , Polycystic kidney disease
,tuberous sclerosis , hereditory
spherocytosis,marfans syndrome,
osteogenesis imperfecta.
 50%
 Either sex.
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4. Spot 2
 39 year old female, 10 weeks pregnant, is concerned
about Downs Syndrome . Which antenatal tests will
you advise?
 Name some other antenatal markers used?
 If mother is a translocation carrier, how much is the
risk to the offspring ?
 Name the associated chromosomes with tranlocation?
 Recurrence risk is highest with which translocation ?
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5.  Chorionic villi sampling[10-12 wk],
amniocentesis[16-20 wk ],cordocentesis [20
wk]
 Triple test [2nd trimester]-low Serum alpha
feto protein, low unconjugated estradiol, high
levels of human chorionic gonadotropin.Fetal
USG-Increased nuchal fold thickness,short
femora.
 10-15 %
 14,15,21,22
 21q/21q [100%]
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6. Spot 3
 Identify the syndrome and State the chromosomal
anomaly
 What is the phenotype in this syndrome ?
 Mention the cardinal features of the syndrome
 Any easy outpatient OPD procedure for the diagnosis
?
 What’s the male version ?
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7.  Turner syndrome
 45 XO
 Female
 Short stature, broad chest with wide
spacing of nipples,congenital
lymphedema,webbed neck,hyperconvex
nails ,ovarian dyegenesis,cubitus
vulgus,short fourth metacarpel,horse
shoe kidney,bicupid aortic valve
 Buccal smear for barr body
 Noonan syndrome
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8.  Which syndrome has this genotype ?
 What is the phenotype ?
 State associated salient features.
Spot 4
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9.  Klinefelter syndrome
 Male
 Hypogenitalism ,hypogonadism ,tall stature
,mental retardation and behavior concerns-
aggressive behavior, antisocial acts, learning
difficulties, anxiety
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10.  Male child with
mental retardation,
 identify the syndrome
 What is the exact locus?
 What is pattern of inheritance ?
 Mention any another syndrome
with similar inheritance
Spot 5
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11.  Fragile X syndrome
 Xq 27.3
 Allelic expansion-change in the increasing size
of a particular DNA sequence from generations
to generations
 Huntington disease, spinocerebellar
ataxia, myotonic dystrophy, DRPLA[dentato
rubro pallido luysian atrophy]
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12.  Identify the pattern of inheritance
 Name 3 conditions of similar inheritance
 Which is the affected sex ?what is the risk
of getting affected in each pregnancy ?
Spot 6
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13.  X – linked recessive
 Hemophilia , color blindness , G6PD
deficiency , DMD, menkes kinky hair
disease, adrenoleukodystrophy
 Male ,the risk is 50% for male child in each
pregnancy.
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14.  Identify the syndrome
 Name the pattern of inheritance
 Give 1 another example of similar inheritance
 What will be the risk of inheritance to
offsprings in affected males with disease
Spot 7
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15.  Incontinentia pigmenti
 X-linked dominant
 Hypophosphatemic rickets, OTC
deficiency, Alport disease
 All the daughters and none of the sons the
of an affected male have disease
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16.  Identify the diagnostic technique
 Name 3 syndromes in which this technique
is used for diagnosis
Spot 8
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17.  FISH
Fluorescent In Situ Hybridization
 Down syndrome
 Prader willi syndrome
 Angel man syndrome
 Williams syndrome
 Miller Dicker syndrome
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18.  State 3 procedures for antenatal genetic
diagnosis ,also mention about the earliest
gestational age at which these tests can be
performed .
 What is the risk of fetal loss ?
 3 common diseases in which antenatal
diagnosis is available
Spot 9
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19.  Amniocentesis –15-16 week of gestation
Chorionic villi sampling –10 12 wks
Cordocentesis –20 wks
Skin biopsy ,liver biopsy
Amniocentesis-0.5-1%
CVS- 1-2%
Down syndrome, DMD, SMA, Beta- Thalassemia
, turner syndrome, XXY
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20.  Name 3 vectors used in gene therapy
 State 3 candidate diseases (with single gene
defects) for gene therapy
Spot 10
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21.  Retrovirus ,adenovirus , adeno associated
virus , naked DNA
 Any chromosomal anomalies ,Severe
combined immunodeficiency,
Cystic fibrosis, hemophilia, PKU,
Gaucher disease, Beta- hemoglobinopathies
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22. 7 year male child with hypotonia and hypogonadism
 Identify the syndrome
and chromosome
involved
 Name the genetic
pattern of inheritance
 Which is the other
syndrome related to
the same chromosome
Spot 11
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23.  Prader willi syndrome ,chromosome 15
 Genetic imprinting / uniparental dizomy
 Angelman syndrome
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24.  Identify the
syndrome
 Which metabolic
problem these
children face ?
 Give three salient
features
 Mention the
chromosome
involved
Spot 12
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25.  Beckwith-Wiedemann syndrome
 Hypoglycemia
 LGA, macroglossia, earlobe
crease, visceromegaly
 Chromosome 11p
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26. Name 3 associated systems involved with 2
conditions in each.
A test you need to do prior to discharge from
hospital – at birth.
Spot 13
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27.  Eyes – cataract, Brushfield spots, myopia,
nystagmus
 Cardiac – Endocardial cushion defect, VSD,
PDA,
 GIT – Duodenal atresia, annular pancrease,
TOF, Hirschsprungs
 Bone – AAD, CDH
 Endocrine – hypothyroid, athyroid
 CNS – delayed development, seizures,
 Thyroid assessment
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28.  Diagnosis
 Name 5 types of
this condition
 What is the urinary
test for diagnosis
 Name 3
metabolites seen in
the urine
 Name the main
organs involved
 What are the Xray
findings called
Spot 14
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29.  Mucopolysaccharidosis
 Hunter, Hurler, Scheie, Sanfillipo,
Matoteaux Lamy, Morquio, Sly
 Urine electrophoresis
 Dermatan, Keratan, Heparan sulphate
 liver, spleen, bone, cornea, hearing,
cardiac
 Dysostosis multiplex
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30.  Diagnosis
 Inheritance
 Incidence of
next sib with
same problem
 Which sex is
involved
Spot 15
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31.  Tuberous sclerosis
 Autosomal recessive
 25%
 Both, equal chances
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32.  Name 3 drugs contraindicated in pregnancy
 Name 3 drug related syndromes with one
associated feature each.
Spot 16
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33.  Alcohol, Warfarin, Valproate, Phenytoin, Methotr
exate, retinoic acid, Lithium
 Fetal alcohol – IUGR, Microcephaly, small
palprebal fissures
 Fetal Hydantoin – growth def., MR, finger and
nail abnormalities
 Fetal Valproate- Dysmorphisms, CVS –
coarctation, spina bifida
 Fetal Warfarin – nasal hypoplasia, stippled
epiphysis, hypoplastic distal limbs
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34. •Diagnosis
•Name 2 more conditions with
•similar features
Spot 17
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35.  Cockaynes syndrome
 Progeria, Wiedeman Syndrome, Werner
syndrome, Rothmund thompson
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36.  Name the abnormality
 Name 2 syndromes with
this feature
 Which other organ
systems would you test
Spot 18
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37.  Bilateral Cleft lip
 Trisomy 13, Cleft lip sequence, fetal
hydantoin, Holoprosencephaly, CHARGE,
Trisomy 18
 All midline structures
 CNS, Cardiac, renal, gonads, ophthal, nose,
umbilicus.
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38.  Diagnosis
 Name 2 more
conditions with
such features
 2 organ systems
for testing
Spot 19
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39.  Proteus syndrome, Maffucis, focal
Hemihypertrophy
 Maffucis, Klippel trenauney syndrome,
Proteus
 Skeletal, brain, skin, Growth, Visera,
Heamat, Vascular
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40.  Diagnosis
 Direct Cause
 Underlying
pathology
 2 other tell
tale signs
Spot 20
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41.  Club foot, eqino varus, amniotic band
sequence, arthogryposis sequence
 Decreased fetal movements in utero
 Congenital CNS/ PNS involvement mainly
nerve, muscle
 Umbilical hernia, undescended testes, weak
cry, poor respiration, dimples
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