med gen concept assessments

Which of the following are the most common cytogenetic abnormalities observed in spontaneously aborted embryos?

T16, T18, Monosomy X, T21, T13

T16, Monosomy X

Normal variant

Features that occur in more than 4% of the population

Major Variant

An anomaly that affects a medically important structure

Minor variant

Anomalies that occur in less than 4% of the population and are of no serious consequence

What is the FIRST test you would recommend for a woman with multiple miscarriages?

karyotype

hypoterlorism

decreased distance between eyes

hypertelorism

increased distance between eyes

strabismus

misalignment of the eyes

ptosis

drooping eyelid

What %ile on a head circumference growth chart is considered macrocephalic?

>97%ile

A 3-year-old boy is referred to the genetics clinic for evaluation of his autistic-like behaviors and cognitive impairment. The test with the highest diagnostic yield is:

chromosomal microarray

T/F: A marker chromosome identified on a karyotype is always of clinical concern.

false

In what type of inheritance will you not see male-to-male transmission?

x-linked

The majority of genetic conditions will manifest during what age range?

pediatric period

Which of the following is an example of incomplete penetrance?

Huntington Disease

Postaxial polydactyly

Neurofibromatosis type 1

Achondroplasia

Postaxial polydactyly

Which of the following is not true regarding HFE-hereditary hemochromatosis?

Is most frequent among individuals of northern European descent

A common treatment is blood letting/phlebotomy

Females may appear to be more severely affected.

It is inherited in an autosomal recessive fashion

Females may appear to be more severely affected.

All of the following are true regarding repeat expansion disorders except:

Nearly every repeat expansion disorder is fully penetrant

Most repeat expansion disorders are neurological in nature

Some disorders have age-dependent penetrance

They can exhibit anticipation

There are conditions with X-linked, autosomal dominant, and autosomal recessive inheritance patterns

Nearly every repeat expansion disorder is fully penetrant

A 4-year-old girl is referred to the genetics clinic to be evaluated because she may have fragile X syndrome. During the appointment, the patient's mother provides information on the family history. Which of the following statements about her daughter's family history is MOST suggestive of fragile X syndrome?

"Her maternal uncle has a son with autism."

"Her father completed the 9th grade and then dropped out."

"Her paternal grandfather and his brother have tremors."

 "Her maternal grandmother went through menopause early."

 "Her maternal grandmother went through menopause early."

what is an example of a major anomaly

cleft palate and CHD

A 50-year-old man has 120 CGG repeats in the FMR1 gene. He is at risk to develop symptoms that could be mistaken for:

Alzheimer disease

Huntington disease

Parkinson disease

Frontotemporal dementia

Parkinson disease

Parkinson disease

Ptosis

drooping eyelid

strabismus

misalingment of the eyes

hypotelorism

decreased distance between eyes

hypertelorism

increased distance between eyes

2,3 syndactyly of the toes is what kind of variant

normal variant

A 3-year-old male patient is being seen for developmental delay and autism spectrum disorder. What is the first-tier testing that would be recommended?

CMA

clinodactyly

digit curves to one side

polydactyly

one or more extra digits

syndactyly

fused digits

ectrodactyly

split hand/foot malformation

what is the microdeletion implicated in DiGeorge syndrome

22q11.2

Which of the following chromosomal aneuploidy syndromes is associated with polydactyly?

T13

Which of the following conditions does not display autosomal dominant inheritance?

Xeroderma pigmentosum

Neurofibromatosis type 1

Myotonic dystrophy

Achondroplasia

Xeroderma pigmentosum

T/F: A consanguineous union involving 2 first cousins is associated with a 10% increased risk of congenital anomalies/recessive conditions above that of the general population

false; First cousins have a 3% increased risk over baseline, Second cousins have a 1% increased risk over baseline

You just found out that your baby sister was diagnosed with cystic fibrosis. You're 18 years old and studying genetics and figured out that there is a BLANK chance that you're a carrier of CF.

2/3

Which of the following conditions are or can be inherited in an X-linked manner?

Rett syndrome

Hemophilia A

Fragile X syndrome

NF1

Rett syndrome

Hemophilia A

Fragile X syndrome

What is the inheritance of retinitis pigmentosa?

X-linked, AR, AD

This disorder that is commonly screened for via genetic carrier screening can also play a role in male infertility as it can cause congenital absence of the vas deferens.

cystic fibrosis

Which of the following conditions are caused by repeat expansions?

Fragile X syndrome

MEN2B

22q11.2 deletion syndrome

Myotonic dystrophy, type 2

Myotonic dystrophy, type 2 and Fragile X syndrome

T/F: A pericentric inversion on chromosome 9 is most likely a variant of no clinical significance.

true, Inv(9)(p11;q13) most commonly observed structurally balanced rearrangement of a chromosome involving heterochromatic region – chromosomally polymorphism of no clinical significance

T/F: Down syndrome is the most common chromosome abnormality in liveborn infants. Nearly 95% of cases that are diagnosed prenatally will survive to term.

false, Approximately 50% of pregnancies with trisomy 21 are miscarried or stillborn prior to term.

Approximately _________% of cases of autism will be caused by an underlying chromosome abnormality that can be detected on microarray.

10-20%

The population incidence of balanced translocations is approximately __________.

1/500

All of the following are polyglutamine disorders except:

Myotonic dystrophy

Spinocerebellar atrophy

Huntington disease

DRPLA

Myotonic dystrophy (3’ UTR region)

What is a hallmark feature of short tandem repeat disorders?

Anticipation

what is the most common inherited ataxia?

friedreich ataxia

Select the conditions that would exhibit elevated serum creatine kinase levels:

Duchenne Muscular Dystrophy

Spinobulbar muscular atrophy/Kennedy disease

Huntington disease

Limb Girdle muscular dystrophy

Spinocerebellar ataxia

Duchenne Muscular Dystrophy

Spinobulbar muscular atrophy/Kennedy disease

Limb Girdle muscular dystrophy

All of the following would typically have symptom onset around age 20-30 with the exception of:

Emery Dreifuss muscular dystrophy

Spinocerebellar ataxia type 2

Limb girdle muscular dystrophy

Facioscapulohumeral muscular dystrophy

Emery Dreifuss muscular dystrophy

T/F: The main health concern for female carriers of DMD is cardiomyopathy.

true

T/F: In patients with Charcot-Marie-Tooth type 1A, the initial presentation is typically pain, numbness, and tremors in the hands and upper limbs.

false; Symptoms in CMT begin in the longer nerves, usually affecting the feet and legs first and the hands and arms later on.

All of the following disorders exhibit genetic heterogeneity with the exception of:

Limb Girdle muscular dystrophy

Emery Dreifuss muscular dystrophy

Charcot Marie Tooth disease

Machado Joseph disease

Machado Joseph disease

T/F: The de novo mutation rate in DMD is about 75%.

false; The de novo mutation rate in DMD is about 33%.

All of the following conditions can have onset early in life. Which one would have the most severe presentation?

Spinal muscular atrophy

Duchenne muscular dystrophy

Fragile X syndrome

Friedreich ataxia

Spinal muscular atrophy

T/F The gene implicated in more than 50% of cases of CMT is PMP22.

true

Which of the following conditions are X-linked?

Becker muscular dystrophy

Emery Dreifuss muscular dystrophy

Rett syndrome

DRPLA

Langer Gideon syndrome

Fragile X syndrome

Becker muscular dystrophy

Emery Dreifuss muscular dystrophy

Rett syndrome

Fragile X syndrome

A patient with progressive muscle weakness, trouble puckering their lips and closing their eyes when they sleep is most likely affected with:

Facioscapulohumeral muscular dystrophy

T/F A female with more than 2 AGG interruptions in the intermediate Fragile X allele has a lower risk of expansion than someone with no AGG interruptions.

true

T/F: Short tandem repeat conditions are always conditions involving trinucleotide repeats.

false; There can be conditions with 4, 5, even 6 tandem repeats

A 50-year-old man has 120 CGG repeats in the FMR1 gene. He is at risk to develop symptoms that could be mistaken for:

parkinson disease

You are seeing an adult patient in clinic with a history of muscle weakness and hearing loss. Upon physical examination, the geneticist notes that the patient cannot pucker lips or purse lips together. What testing would you recommend sending first?

neuromuscular panel

T/F: The first symptom in Huntington disease is usually chorea. 

false

T/F The majority of short tandem repeat disorders are hereditary in nature (vs. de novo). 

true

T/F In Fragile X, AGG repeats stabilize the expanded region during transmission for women with intermediate/gray zone alleles.

true

T/F Spinal muscular atrophy is often screened for on carrier screening panels. 

true

T/F The cause of death in Friedrich's ataxia is typically heart failure.

true

Myotonic dystrophy type 1 gene

DMPK

Huntington disease gene

HTT

Friedrich’s ataxia gene

FXN

Charcot-Marie-tooth type 1A gene

PMP22

Fragile X gene

FMR1

Pes planus

flat foot

pes cavus

high arch foot

chorea

spasmic, involuntary movements of limbs or facial muscles

nystagmus

involuntary movements of the eyes

dysarthria

difficulty speaking

Dyspnea

difficulty breathing

Dysphagia

difficulty swallowing

The microdeletion in DiGeorge/Velocardiofacial syndrome is

22q11.2

what is the most common microdeletion

22q11.2 deletion syndrome (DiGeorge)

T/F: You can easily diagnose autism spectrum disorder through genetic testing.

Williams syndrome defining characteristic

Cocktail party personality

Smith-Magenis syndrome defining characterisitc

inverted circadian rhythm of melatonin

Cri du Chat syndrome defining characteristic

high pitched crying

Wolf-Hirschorn syndrome defining characteristic

greek warrior helmet appearance

You are seeing a 3-year-old male in clinic due to developmental delay, supravalvar aortic stenosis, and a history of hypercalcemia. What testing would you recommend as the FIRST test to determine a diagnosis?

SNP Microarray

T/F:Miller Dieker syndrome is also known as trichorhinophalangeal syndrome type 2.

false; thats Langer-Gideon syndrome

What gene is associated with lissencephaly in Miller Dieker syndrome?

LIS1

What tumor can be seen in WAGR?

Wilms tumor

You are seeing a patient in clinic due to developmental delay, sleep disturbance, and short stature. You are suspicious of Smith-Magenis syndrome, however, the SNP array came back normal. What gene would you recommend sequencing as the next diagnostic step?

RAI1

What can be a cause of Prader-Willi syndrome?

paternal deletion of 15q11.2q13

Maternal UPD

Imprinting center defect

Which of the following testing options can detect 22q11.2 deletion syndrome? Select all that apply.

Exome sequencing

FISH for 22q

Karyotype

SNP microarray

FISH, SNP microarray

T/F:Women with premutations in FMR1 are NOT at risk to develop FXTAS.

false

what clinical features can be seen in a majority of patients with classic Rett syndrome?

Regression of developmental skills

Stereotypic hand movements

what clinical features is commonly seen in Rubenstein-Taybi syndrome?

Broad thumbs and halluces

DiGeorge deletion location

22q11.2

Williams Syndrome Deletion location

7q11.23

Wolf-Hirschorn Syndrome deletion location

4q16.3

You are seeing a 3-year-old male patient for a history of autism. Upon physical examination, he was found to be macrocephalic. What other finding on physical exam would be most suggestive of PTEN hamartoma tumor syndrome?

Freckling of the penis