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Flashcards in Genetics Deck (218):
1

What are some common facial features of turners syndrome?d

Low hairline, Webbed neck, small mandible, high arched palate and low set ears

2

How might an adolescent with turners syndrome present ?

Short stature, minimal breast development and primary amenorrhea

3

What cardiac abnormality is associated with turners syndrome?

Bicuspid aortic valve or coarctation

4

What are the chances of turners syndrome in a woman with advanced age?

The same as the normal palpitation! A chromosome deletion is not associated with advanced maternal age (only trisomys are increased)

5

How do you diagnose turners and what test is inadequate ?

Need karyotype - if mosaicism, karyotype may be normal but FISH can detect mosaicism
Buccal smear inaccurate

6

What is the genetic defect in cri du chat?

Deletion of the short arm of chromosome 5

7

What is the difference between apert syndrome and crouzon syndrome?

Both have craniosynostosis but only apert presents with syndactyly

8

What features of noonan syndrome differentiate from Turner syndrome?

Noonan syndrome has pectus excavatum and pulmonic stenosis
Karyotype is normal!!

9

What is the inheritance of crouzon syndrome?

Autosomal dominant

10

A child presents with craniosynostosis, prominent forehead, proptosis and a beak nose, what syndrome should you consider?

Crouzon syndrome

11

You are presented with a tall male with small testes who is socially awkward, what should you test for?

Klinefelters - chromosome analysis

12

Which age group gives birth to the most amount of trisomies?

Women in their 20s

13

What is the most common abnormality in children with Down syndrome?

Hypotonia

14

If a mother has a full translocation of chromosome 21, what are the chances her child will have Down syndrome?

100%

15

If a child has trisomy without translocation of chromosome 21, what are the chances the mother will have another chicks with Down syndrome?

1% plus the age related risk

16

If an infant had a partial translocation of chromosome 21, what are the chances of recurrence based on which parent the defect came from?

The partial translocation has a higher chance of recurrence if it is from the father

17

What is the age related risk of trisomy 21 in a 22 year old mother?

1/1500

18

What is the age related risk of developing Down syndrome in a child born to a 40y/o mother?

1/90

19

Children with Down syndrome are at increased risk for what 4 conditions?

Leukemia
Duodenal atresia
Endocardial cushion defects
Atlantoaxial instability

20

What are the signs/symptoms of trisomy 13?

"BAD LUCK"
Brain lesions (microcephaly / holoprosencrphaly)
Abnormally low ears
Digits (polydactyly)
Leukocyte with nuclear projections
Uterus bicornuate or hypoplastic ovaries
Cleft lip/palate
Kidneys (cystic)

21

What abnormalities exist in the extremities of a patient with Down syndrome?

5th digit dysplasia
Simian crease
Hyperextensible joints
Wide gap between 1st and 2nd toe

22

What syndrome would you consider in a patient with atrial septal defect and upper limb defects including three jointed thumbs?

Holt Oram syndrome

23

What syndrome should you consider in a child with self mutilation and choreiform movements?

Lesch nyhan syndrome

24

What lab abnormalities would you find in a child with lesch nyhan?

Elevated uric acid

25

A patient presents with rocker bottom feet and clenched fists, what syndrome should you consider?

Trisomy 18

26

What abnormal facial features would you find in trisomy 18?

Prominent occiput and low set ears

27

What organs might be found to be abnormal in a child with trisomy 18?

Horseshoe kidneys

28

What syndrome should you consider in a child with cafe au lait spots, fibrous dysplasia and precocious puberty?

Mccune Albright syndrome

29

What two syndromes show genetic imprinting and how?

Angelman - chromosome 15 (deletion from mom and 2 copies from dad)
Prader Willi - chromosome 15 (deletion from dad and 2 copies from mom)

30

What syndrome should you consider in a patient severe developmental delay, movement disorders and excessive laughing?

Angelman syndrome

31

What syndrome should you consider in a patient who is obese with small hands and testicles?

Prader Willi

32

What autosomal recessive disorder is characterized by progressive CNS, oohthalmologic and endocrine problems?

Laurence moon syndrome

33

What are the similarities and differences between Prader Willi and Laurence moon syndrome ?

Both have obesity and hypogonadism but only Laurence moon causes syndactyly and retinal dystrophy

34

What syndrome is associated with omphalocele, Macroglossia, hypospadias, hypoglycemia and hemihypertrophy?

Beckwith wiedemann

35

How do you test for digeorge syndrome?

Chromosomal analysis won't detect the micro deletion - need FiSH study

36

If mother is a carrier if an X linked recessive disorder, what are the chances she will have an affected child?

25% will have disease
25% will be carriers

37

What are the chances that a mother who is a carrier of an x linked recessive disorder will have an affected male child?

50% will be affected

38

Can a female be affected by an X linked recessive disorder?

No! They can only be carriers!

39

What type of inheritance is androgen insensitivity?

X linked recessive

40

What type of inheritance is wiskott Aldrich?

X linked recessive

41

What type if inheritance is retinitis pigmentosa?

X linked recessive

42

What type of inheritance is nephrogenic diabetes insipidus?

X linked recessive

43

What type if inheritance is duchenne muscular dystrophy ?

X linked recessive

44

What type of inheritance is chronic granulomatous disease?

X linked recessive

45

What type of inheritance is hemophilia?

X linked recessive

46

What type of inheritance is G6PD deficiency ?

X linked recessive

47

What is the only x linked recessive disorder that can be found in a female?

Androgen insensitivity - patient is phenotypically female but is genetically XY

48

What are the 4 X linked dominant disorders?

X linked hypophospatemic rickets
Pseudohyperparathyroidism
Acardi syndrome
Alport syndrome

49

In what syndrome do patients present with macrocephaly, ocular abnormalities and absent corpus callosum?

Aicardi syndrome

50

What type of inheritance is peutz jeghers syndrome?

Autosomal dominant disorder

51

What type of inheritance is Von willebrand disease?

Autosomal dominant disorder

52

What type of inheritance is Huntington chorea?

Autosomal dominant disorder

53

What type of inheritance is waardenburg syndrome?

Autosomal dominant disorder

54

What type of inheritance is Gardner syndrome?

Autosomal dominant disorder

55

What type of inheritance is Marfan syndrome ?

Autosomal dominant disorder

56

What type of inheritance is neurofibromatosis?

Autosomal dominant disorder

57

What type of inheritance is retinoblastoma?

Autosomal dominant disorder

58

What type of inheritance is achondroplasia ?

Autosomal dominant disorder

59

What type of inheritance is tuberous sclerosis?

Autosomal dominant disorder

60

What type of inheritance are the porphyrias?

Autosomal dominant disorder

61

What type of inheritance is galactosemia?

Autosomal recessive

62

What type if inheritance is alpha 1 anti trypsin deficiency ?

Autosomal recessive

63

What type if inheritance is sickle cell disease and thalassemia?

Autosomal recessive

64

What type of inheritance are hurlers and Tay Sachs disease?

Autosomal recessive

65

What type of inheritance is ataxia telangiectasia?

Autosomal recessive

66

What type of inheritance is Wilson disease?

Autosomal recessive

67

What type of inheritance is PKU?

Autosomal recessive

68

What type of inheritance is kartagener syndrome ?

Autosomal recessive

69

When can chorionic villus sampling be performed?

12 weeks

70

When can amniocentesis be performed?

16 weeks

71

What is the best test in predicting fetal lung maturity? Why?
When is this test NOT accurate?

Phosphatidylglycerol - absent prior to 35 weeks gestation
Not reliable if diabetes - need total surfactant activity

72

What are the common findings in fetal alcohol syndrome ?

Short philtrum, thin upper lip, facial hypoplasia, short palpebral fissure and small 5th fingernail

73

What symptoms are associated with teratogenic exposure to anticonvulsants?

Microcephaly
IUGR
Cardiac defect
Cleft lip
Hypospadias
Cryptorchidism
Club foot
Cardiac defect

74

What effects can lithium have on the developing fetus?

Ebsteins anomaly

75

What 5 things can occur to a fetus when mother is taking isotretinoin?

Microcephaly
Micropthalmia
Hypoplastic ears
Truncus arteriosis
Absent thymus

76

What specific defects are associated with carbamazepine during pregnancy ?

Spina bifida
Facial deformities

77

What specific defects are seen with phenytoin in pregnancy?

Finger stiffness
Nail hypoplasia
Cardiac anomalies
skeletal anomalies
Ophthalmology anomalies

78

What specific defects are associated with valproic acid during pregnancy?

Neural tube defects

79

What anatomical defects are associated with warfarin use during pregnancy?

Depressed nasal bridge
Hypoplastic distal phalanges
Stippled epiphyses

80

What fetal defects are found with ace inhibitor use during pregnancy?

Anuria
Oligohydramnios
Skull hypoplasia
Fetal hypotension

81

What is the charge association?

Coloboma & cognitive defects
Heart disease
Atresia choanal
Retarded growth
GU abnormalities
Ear anomalies

82

What is associated with the VACTERL syndrome?

Vertebral defects
Anal atresia
Cardiac defects (VSD)
TE fistula
Renal defects
Limb abnormalities

83

What is potter syndrome?

Oligohydramnios sequence = hypoplastic lungs, limb malformations (club feet, excess skin on hands), renal agenesis and IUGR

84

In what condition might the fetal membranes be covered in yellow nodules (amnion nodosum)?

Oligohydramnios (potter) sequence

85

In what syndrome do patients present with a broad thumb and cryptorchidism?

Rubinstein taybi syndrome

86

In what syndrome do patients present with broad thumbs and wide spaces eyes?

Pfeiffer syndrome

87

In what syndrome do patients present with a small chin and growth retardation?

Russell silver syndrome

88

What defects are associated with prune belly syndrome?

Bladder outlet obstruction
Oligohydramnios
Pulmonary hypoplasia
Undescended testes

89

What type or inheritance is treacher Collins?

Autosomal dominant

90

What syndrome is associated with conductive hearing loss, small jaw and low eyelid abnormalities?

Treacher Collins

91

What type of intelligence should you consider in a patient with small jaw and multiple family members with hearing aids ?

Treacher Collins - normal intelligence

92

What should you think of in a patient with intellectual disability with hx infantile spasms?

Tuberous sclerosis

93

What type of neurological abnormality might you expect in a patient with rhizomelic shortening and large heads?

Nerve root compression in small foremen magna in patient with achondroplasia

94

What syndrome would you suspect in a patient with elfin face, wide spaced teeth and upturned nose who is very friendly?

Williams syndrome

95

What lab or anatomical defect is associated with Williams syndrome?

Hypercalcemia
Supravalvular aortic stenosis

96

What is the most common inherited form of intellectual disability?

Fragile X

97

what is the chromosome abnormality in fragile X?

Repeat of CGG trinucleotide on X chromosome

98

What is the most common cause of genetic disability?

Down syndrome

99

What syndrome would you suspect in a male with large ears, macroorchidism and wierd behavior?

Fragile X syndrome

100

What syndrome presents with thick skull, corneal clouding and coarse facial features as well as intellectual disability ?

Hurler syndrome

101

What are the similarities and differences between hurler's and hunter's syndrome?

Both have hepatosplenomegaly and progressive deafness
Hunters syndrome does NOT have corneal clouding and children are short

102

What type of inheritance is hunters syndrome?

X linked recessive

103

What testing is appropriate for diagnosing fragile X?

DNA testing is more sensitive than karyotype

104

What would you consider in a patient with regression of developmental milestones and wringing hands?

Rett syndrome

105

How do females with Rett syndrome regress?

Head growth decelerates at 4 months
Stagnation of development from 6-18 months
Loss of milestones between age 1-4 then no further decline

106

What syndrome presents with pointed nose, bird like face and small eyes?

Hallermann streiff syndrome

107

How is peutz jeghers syndrome inherited?

Autosomal dominant

108

What syndrome should you suspect with mucosal pigmentation of lips and gums and hamartomatous polyps in intestines?

Peutz Jeghers syndrome

109

What is the appropriate treatment for peutz jeghers syndrome ?

Removal of polyps

110

What syndrome should you consider in a patient with small chin, big tongue relative to chin, cleft palate and micrognathia?

Pierre Robin sequence

111

What extremity anomalies are common with Pierre Robin?

Syndactyly, clinidactyly, spinal deformities and hip anomalies

112

Does Pierre Robin sequence have developmental or neurological problems ? If so, what?

Language/motor delay
seizures

113

What cardiopulmonary abnormality may occur in Pierre Robin and why?

Cor pulmonale due to upper airway obstruction

114

What is the first treatment for a patient with sturge weber? Why?

Ophthalmology referral to rule out glaucoma or urgent eye problems

115

What syndrome should you suspect in a patient with port wine stain, developmental delay, seizure, hemipenis and vision problems?

Sturge weber

116

What syndrome should you suspect in a patient with port wine stain, developmental delay, seizure, hemipenis and vision problems?

Sturge weber

117

What is the first treatment for a patient with sturge weber? Why?

Ophthalmology referral to rule out glaucoma or urgent eye problems

118

What cardiopulmonary abnormality may occur in Pierre Robin and why?

Cor pulmonale due to upper airway obstruction

119

Does Pierre Robin sequence have developmental or neurological problems ? If so, what?

Language/motor delay
seizures

120

What extremity anomalies are common with Pierre Robin?

Syndactyly, clinidactyly, spinal deformities and hip anomalies

121

What syndrome should you consider in a patient with small chin, big tongue relative to chin, cleft palate and micrognathia?

Pierre Robin sequence

122

What is the appropriate treatment for peutz jeghers syndrome ?

Removal of polyps

123

What syndrome should you suspect with mucosal pigmentation of lips and gums and hamartomatous polyps in intestines?

Peutz Jeghers syndrome

124

How is peutz jeghers syndrome inherited?

Autosomal dominant

125

What syndrome presents with pointed nose, bird like face and small eyes?

Hallermann streiff syndrome

126

How do females with Rett syndrome regress?

Head growth decelerates at 4 months
Stagnation of development from 6-18 months
Loss of milestones between age 1-4 then no further decline

127

What would you consider in a patient with regression of developmental milestones and wringing hands?

Rett syndrome

128

What testing is appropriate for diagnosing fragile X?

DNA testing is more sensitive than karyotype

129

What type of inheritance is hunters syndrome?

X linked recessive

130

What are the similarities and differences between hurler's and hunter's syndrome?

Both have hepatosplenomegaly and progressive deafness
Hunters syndrome does NOT have corneal clouding and children are short

131

What syndrome presents with thick skull, corneal clouding and coarse facial features as well as intellectual disability ?

Hurler syndrome

132

What should be done in a patient with ammonia between 200-600?

Benzoate and phenylacetate

133

What should be done if an infant had an ammonia level of >600?

Dialysis

134

What inborn errors of metabolism present with normal ABG and normal ammonia ?

Aminoacidopathy
Galactosemia
Non-Ketotic hyperglycemia

135

What inborn errors of metabolism are associated with normal ABG but elevated ammonia?

Urea cycle defect
Transient hyperammonemia

136

What inborn error of metabolism is associated with metabolic acidosis and high ammonia?

Propionic acidemia
Methylmalonic acidemia
Fatty acid oxidation defects

137

What inborn error of metabolism is associated with metabolic acidosis and normal ammonia?

Maple syrup urine disease

138

What is the normal serum ammonia value for a newborn?

<110

139

What might be the difference between an inborn error of metabolism and brain tumor in the history?

Brain tumor will have progressively worsening symptoms

140

What should be the first step after diagnosis of an organic acidemia?

Rehydration

141

What lab should be done in a 2 day old infant with acidosis, ketosis and high serum ammonia?

Urine organic acid levels

142

If you are presented with a patient who appears septic but is afebrile, what lab should be performed?

Serum ammonia , lactic acid, pyruvate, carnitine or acetylcarnitine

143

What should you consider in a patient with metabolic acidosis and bone marrow suppression?

Bone marrow suppression can occur with organic acidemias

144

What condition is associated with lethargy, poor feeding, seizures and odor of sweaty feet?

Isovaleric acidemia

145

What is the treatment of isovaleric acidemia?

Protein restriction

146

What treatment should be given for methylmalonic acidemia?

Vitamin B12

147

What is the inheritance pattern of fatty acid oxidation defects?

Autosomal recessive

148

How can you diagnose fatty acid oxidation defects?

Normal serum amino acids
NO reducing substances or ketones in urine
Plasma acylcarnitine profile

149

What condition would you consider in an infant with hypoglycemia and hepatomegaly after a benign illness?

Fatty acid oxidation defect

150

How are urea cycle defects treated?

Reducing protein intake and increasing glucose by IV

151

What do you do for a patient diagnosed with urea cycle defect who has ketonuria?

Think of a different diagnosis - possibly organic acidemias

152

What diagnosis should you consider in a patient hypotonia and dysmorphic features but normal ammonia?

Zellweger

153

What might be the diagnosis in a patient who was born normal but then developed abdominal distention, hypoglycemia and non-glucose reducing substances in the urine?

Galactosemia

154

What is the defect in patients with galactosemia? How do you diagnosis?

Deficiency of galactose 1 phosphate uridyltransferase (diagnose by measuring GALT in RBCs)

155

How do you treat galactosemia ? Why is it important to treat?

Galactose free diet - cataracts are reversible with diet change

156

Which symptom of galactosemia can be reversible with dietary changes?

Cataracts

157

What type of infections are common in children with galactosemia ?

Gram negative organisms such as E. coli

158

What is the treatment for children who have seizures after each meal? What disease is this?

Avoidance of fructose (disease is inherited fructose intolerance)

159

Infants of diabetic mothers are at high risk for what 4 endocrine conditions?

Hypoglycemia
Hyperbilirubinemia
Hypocalcemia
Polycythemia

160

What disease should you consider in a patient with hypoglycemia, acidosis, increased tone and seizures ?

Maple syrup urine disease

161

What condition presents with Macrosomia, microcephaly, Macroglossia and ohphalocele?

Beckwith wiedemann

162

What condition should you consider in a patient with hypoglycemia and ketonuria?

Adrenal insufficiency

163

Why do patients with beckwith wiedemann develop hypoglycemia?

Islet cell hyperplasia

164

What is the best medication for refractory hypoglycemia? (Resistant to insulin)

Diazoxide

165

What condition should you consider in a patient with lactic acidosis, rash, alopecia and neurological symptoms ?

Biotinidase deficiency

166

Which amino acids are elevated in patients with maple syrup urine disease?

Valine
Isoleucine
Alloisoleucin
Leucine

167

What test should you order in a patient with hypoglycemia, hepatomegaly and seizures?

Urine ketones and reducing substances

168

How is alcaptonuria treated?

Low phenylalanine and tyrosine diet

169

What disease causes "dark diaper" and why?

Alcaptonuria - homogentisic acid in the urine

170

Children with alcaptonuria may also have what conditions?

Arthritis and heart disease (but normal intelligence)

171

What condition presents with corneal ulcerations & plaques and thickened skin on the soles of the feet?

Oculocutaneous tyrosinemia

172

What amino acids are elevated in homocystinuria? And why?

Elevated methionine

173

What condition presents with dislocated lenses, skeletal abnormalities, light skin tone and cognitive defects?

Homocystinuria

174

What is the treatment for homocystinuria?

Pyridoxine OR diet of high cystine and low methionine

175

What is the difference between Marfan syndrome and homocystinuria ?

Marfan syndrome does NOT have cognitive defects but homocystinuria does
Marfan has anterior lens displacement but homocystinuria has posterior displacement

176

Patients with homocystinuria are at risk for what complications ?

Thrombi and emboli including PE

177

When should PKU screening be performed?

After first protein containing feeds

178

What disease should you consider in a patient who was normal at birth but at 3 months of age developed vomiting, eczema and mousy smelling urine?

PKU

179

Patients with PKU will develop what problems if they are left untreated?

Microcephaly
Low weight
Congenital heart disease
Profound intellectual disability

180

What is the treatment of PKU?

Low phenylalanine formula (lofenalac) and adequate tyrosine intake

181

What should a mother with PKU do prior to becoming pregnant? And why?

Low phenylalanine diet to prevent miscarriage, SGA, cardiac defects and intellectual disability

182

What lab findings may be present in children with hurler syndrome?

Reduced Alpha L iduronidase in WBCs

183

What syndrome presents with facial coarsening, hepatosplenomegaly and corneal clouding?

Hurlers syndrome

184

What is the transmittance of hurlers and hunters syndrome?

Hunters is X linked recessive
Hurlers is autosomal recessive

185

What lab findings are found in hunters syndrome ?

Low iduronate sulfatase enzyme activity

186

What disease presents with organomegaly, coarse facial features, joint contractures and pebbly skin?

Hunter syndrome

187

Which mucopolysaccharidosis presents with cognitive defects and minimal facial corsening?

Sanfilippo sundrome

188

What is an abnormal lab finding in sanfilippo syndrome ?

Urine with increased heparan sulfate

189

What condition presents with skeletal abnormalities, corneal clouding and normal intelligence?

Morquio syndrome

190

What condition presents with club feet, hip dislocation, joint contractures and severe intellectual disability ?

I-cell disease (mucolipidosis 2)

191

What are two purine and pyrimidine disorders?

Adenosine deaminase deficiency and lesch nyhan syndrome

192

What is the treatment for Von gierke disease?

Frequent meals and avoidance of fasting
Glucose infusion until age 2, then cornstarch is used

193

What is the underlying metabolic cause of Von gierke disease ?

Deficiency of hepatic glucose 6 phosphatase

194

What condition should you consider in a patient with doll-like face, hypoglycemia, hepatomegaly and high cholesterol?

Von gierke disease aka glycogen storage disease type 1

195

What lab findings are abnormal in Von Gierke disease?

Hypoglycemia with fasting
Elevated lactic acid and uric acid

196

What is the underlying metabolic cause of pompe disease?

Deficiency in lysosomal breakdown of glycogen

197

What disease should you consider in a one month old infant who suddenly becomes floppy with FTT, hypotonia, hard muscles, Macroglossia and hepatomegaly ?

Pompe disease aka glycogen storage disease type 2

198

What condition presents in a newborn after having his first protein containing feed who becomes lethargic and comatose ?

Non-Ketotic hyperglycinemia

199

Why is familial hypercholesterolemia associated with obesity?

It is not! It is due to deficiency of LDL receptors

200

What disease presents with an infant who is very thin and long die to fat tissue that is resistant to insulin?

Congenital lipodystrophy

201

What three conditions present with cherry red spot of the retina ?

Farber disease
Tay Sachs
Niemann pick

202

What disease presents with skin nodules and painful joints in the first week of life?

Farber disease

203

What disease presents with triglyceride and cholesterol esters deposited in the body tissues and calcified adrenal glands?

Wolman disease

204

What is the cause of menkes kinky hair syndrome ?

Low serum copper and low serum ceruloplasmin with high tissue copper

205

What disease presents with jaundice, hepatomegaly and neurological symptoms?

Wilson's disease

206

What eye findings are common in Wilson's disease ?

Kayser fleischer rings
But normal vision

207

How do you diagnose Wilson disease?

Liver biopsy

208

What disease presents with a child who was normal until age 2 when he developed hepatosplenomegaly, bone pain and easy bruising?

Gaucher disease

209

What X-ray findings may be seen in gaucher disease?

Osteosclerosis and lyric lesions

210

What is chronic juvenile gaucher disease?

Less severe form of gaucher with splenomegaly and thrombocytopenia but no CNS involvement

211

What disease presents with orange skin lesions, eye opacities and vascular disease of the kidney, heart and brain?

Fabry (a lysosomal lipid storage disease aka sphingolipidoses)

212

What is krabbe disease?

A sphingolipidoses with Demyelination with progressive degeneration resulting in death by age two

213

What is the underlying metabolic disorder that causes Tay Sachs disease?

Deficiency of hexosaminidase A

214

What disease presents with a normal child until age 9 months who develops lethargy, hypotonia, exaggerated startle reflex, macrocephaly and progressive neurological degeneration and death by age 5 ?

Tay Sachs

215

How can you screen for Tay Sachs disease?

Amniocentesis or CVS sampling

216

What is the difference between Tay Sachs and Niemann pick?

Both have cherry red spots but only Niemann pick has hepatosplenomegaly

217

What may cause a false positive PKU result on newborn screening? When should you suspect this?

Deficiency of teyrahydrobiopterin (bH4) - consider this if the patient remains symptomatic despite treatment for PKU

218

What might be the presenting signs of Turner syndrome in an infant?

Short 4th/5th metacarpal bones, wide spaced nipple or lymphedema hands/feet