Question 1

Mutations in the encoding of histone-modifying proteins have been shown to influence the development of what congenial condition?&#10;A) Cleft palate&#10;B) Acephalous&#10;C) Heart disease&#10;D) Webbed digits

Accepted Answer

Mutations in genes that encode histone-modifying proteins have been implicated in congenital heart disease.Research has yet to provide a relationship between abnormal histone-modifying proteins and cleft palate, acephalous, and webbed digits.

Question 2

What is the role of inactive MLH1 in the development of some forms of inherited colon cancer?&#10;A) Deletion of a nucleotide repeat in the DUX4 gene.&#10;B) DNA damage is left unrepaired.&#10;C) Expansion in the number of cytosine-guanine (CG) dinucleotide.&#10;D) Abnormalities of chromosome 11p15.5 that lead to downregulation of IGF2.

Accepted Answer

A major cause of one form of inherited colon cancer (hereditary nonpolyposis colorectal cancer [HNPCC])is the methylation of the promoter region of a gene, MLH1, whose protein product repairs damaged DNA.When MLH1 becomes inactive, DNA damage accumulates, eventually resulting in colon tumors.Facioscapulohumeral muscular dystrophy (FSHMD)is associated with the DUX4 gene.Fragile X is associated with the cytosine-guanine (CG)dinucleotide.Downregulation of IGF2 is associated with Russell-Silver syndrome.

Question 3

Screening tools that are epigenetically based have shown promise in diagnosing which types of cancer? (select all that apply)&#10;A) Colon&#10;B) Breast&#10;C) Skin&#10;D) Bladder&#10;E) Prostate

Accepted Answer

Monitoring for misregulation of miRNAs has shown promise as a tool for early diagnosis of cancers of the colon, breast, and prostate.Other epigenetics-based screening approaches have shown promise for detection of cancers of the bladder, lung, and prostate.Such screenings have not yet been developed for skin cancers.

Question 4

What comorbid condition does an individual diagnosed with Beckwith-Wiedemann syndrome have an increased risk of developing?&#10;A) Cancer&#10;B) Diabetes&#10;C) Depression&#10;D) Food allergies

Accepted Answer

Beckwith-Wiedemann syndrome is accompanied by an increased predisposition to cancer.There is no current correlation between Beckwith-Wiedemann syndrome and diabetes, depression, or food allergies.

Question 5

When considering abnormal epigenetic modifications, what factor is currently being viewed as strongly associated with the development of some cancers?&#10;A) Family genetics&#10;B) Lifestyle choices&#10;C) Environmental stressors&#10;D) Emotional coping skills

Accepted Answer

Environmental stressors can markedly increase the risk of aberrant epigenetic modification and are strongly associated with some cancers.While genetics, lifestyle choices, and coping skills can affect the development and management of cancer, they are not currently considered as being the primary factors in the epigenetic modification that occurs.

Question 6

What characteristic of Prader-Willi syndrome is not a characteristic of Angelman syndrome?&#10;A) It is inherited from the father.&#10;B) Mental retardation is observable.&#10;C) Imprinting of an abnormal chromosome 15.&#10;D) Seizure disorder is present.

Accepted Answer

A well-known disease example of imprinting is associated with a deletion of about 4 million base (Mb)pairs of the long arm of chromosome 15.When this deletion is inherited from the father, the child manifests Prader-Willi syndrome, whose features include short stature, hypotonia, small hands and feet, obesity, mild to moderate mental retardation, and hypogonadism.The same 4 Mb deletion, when inherited from the mother, causes Angelman syndrome, which is characterized by severe mental retardation, seizures, and an ataxic gait.

Question 7

Research has demonstrated that neural stem cells have an impaired ability to differentiate into functional neurons when subjected to:&#10;A) ethanol.&#10;B) marijuana.&#10;C) insufficient nutrients.&#10;D) poor oxygenation.

Accepted Answer

It has been found that treating cultured neural stem cells with ethanol impairs their ability to differentiate to functional neurons; this impairment seems to be correlated with aberrant, dense methylation at loci that are active in normal neuronal tissue.The research does not support the effects of marijuana, insufficient nutrition, or poor oxygenation on the stem cell's ability to differentiate appropriately.

Question 8

Which embryonic stem cell characteristic is referred to as totipotent?&#10;A) Ability to differentiate into any type of somatic cell.&#10;B) Ability to repair its own damaged DNA.&#10;C) Ability to determine which parental chromosome copy it will imprint.&#10;D) Ability to minimize the impact of poor in utero nutrition.

Accepted Answer

Each of the cells in the very early embryo has the potential to give rise to a somatic cell of any type. These embryonic stem cells are therefore said to be totipotent (“possessing all powers”). The term totipotent does not infer the ability to repair damaged DNA, select specific chromosome copies, or adjust for poor in utero nutrition.

Question 9

Research has provided support for the theory that epigenetic modifications can result from deficient in utero nutrition causing which chronic disease? (select all that apply)&#10;A) Obesity&#10;B) Asthma&#10;C) Cardiovascular disease&#10;D) Diabetes&#10;E) Crohn's disease

Accepted Answer

When researchers sought to investigate how exposure to famine in utero had impacted individuals born in a historically prosperous country whose nutritional intake was dramatically impacted by WWII, they found that individuals who suffered nutritional deprivation in utero were more likely to suffer from obesity and diabetes as adults than individuals who had not experienced nutritional deprivation during gestation.Other data sets reveal elevated risk of cardiovascular and metabolic disease for offspring of individuals exposed during early development to fluctuations in agricultural yields.The research does support the development of asthma or Crohn's disease.

Question 10

During which stage of human development does the role of epigenetics have the greatest impact on the development of epigenetic abnormalities?&#10;A) Infancy&#10;B) Puberty&#10;C) In utero&#10;D) Middle age

Accepted Answer

Conditions encountered in utero, during childhood, and even during adolescence or later can have long-term impacts on epigenetic states, which sometimes can be transmitted across generations.The impact is not supported for the periods of infancy, puberty, and middle age.

Question 11

Housekeeping genes are vital to the function and maintenance of all the body's cells.What characteristic is associated with these genes?&#10;A) They lack encoding histones.&#10;B) They are transcriptionally active.&#10;C) Ribosomal RNA genes are absent.&#10;D) Epigenetic silencing has occurred.

Accepted Answer

The answer of Housekeeping genes are vital to the function...

Deck 3: Epigenetics and Disease