Genetics Flashcards
(218 cards)
1
Q
What are some common facial features of turners syndrome?d
A
Low hairline, Webbed neck, small mandible, high arched palate and low set ears
2
Q
How might an adolescent with turners syndrome present ?
A
Short stature, minimal breast development and primary amenorrhea
3
Q
What cardiac abnormality is associated with turners syndrome?
A
Bicuspid aortic valve or coarctation
4
Q
What are the chances of turners syndrome in a woman with advanced age?
A
The same as the normal palpitation! A chromosome deletion is not associated with advanced maternal age (only trisomys are increased)
5
Q
How do you diagnose turners and what test is inadequate ?
A
Need karyotype - if mosaicism, karyotype may be normal but FISH can detect mosaicism
Buccal smear inaccurate
6
Q
What is the genetic defect in cri du chat?
A
Deletion of the short arm of chromosome 5
7
Q
What is the difference between apert syndrome and crouzon syndrome?
A
Both have craniosynostosis but only apert presents with syndactyly
8
Q
What features of noonan syndrome differentiate from Turner syndrome?
A
Noonan syndrome has pectus excavatum and pulmonic stenosis
Karyotype is normal!!
9
Q
What is the inheritance of crouzon syndrome?
A
Autosomal dominant
10
Q
A child presents with craniosynostosis, prominent forehead, proptosis and a beak nose, what syndrome should you consider?
A
Crouzon syndrome
11
Q
You are presented with a tall male with small testes who is socially awkward, what should you test for?
A
Klinefelters - chromosome analysis
12
Q
Which age group gives birth to the most amount of trisomies?
A
Women in their 20s
13
Q
What is the most common abnormality in children with Down syndrome?
A
Hypotonia
14
Q
If a mother has a full translocation of chromosome 21, what are the chances her child will have Down syndrome?
A
100%
15
Q
If a child has trisomy without translocation of chromosome 21, what are the chances the mother will have another chicks with Down syndrome?
A
1% plus the age related risk
16
Q
If an infant had a partial translocation of chromosome 21, what are the chances of recurrence based on which parent the defect came from?
A
The partial translocation has a higher chance of recurrence if it is from the father
17
Q
What is the age related risk of trisomy 21 in a 22 year old mother?
A
1/1500
18
Q
What is the age related risk of developing Down syndrome in a child born to a 40y/o mother?
A
1/90
19
Q
Children with Down syndrome are at increased risk for what 4 conditions?
A
Leukemia
Duodenal atresia
Endocardial cushion defects
Atlantoaxial instability
20
Q
What are the signs/symptoms of trisomy 13?
A
"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
Q
What abnormalities exist in the extremities of a patient with Down syndrome?
A
5th digit dysplasia
Simian crease
Hyperextensible joints
Wide gap between 1st and 2nd toe
22
Q
What syndrome would you consider in a patient with atrial septal defect and upper limb defects including three jointed thumbs?
A
Holt Oram syndrome
23
Q
What syndrome should you consider in a child with self mutilation and choreiform movements?
A
Lesch nyhan syndrome
24
Q
What lab abnormalities would you find in a child with lesch nyhan?
A
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
