問題詳情

III. Discourse(每格1.25分)Brain conditions such as schizophrenia and autism spectrum disorder have long been known to havean inherited component. (20)D Now, some of the first findings from the most comprehensivegenomic analysis of the human brain ever undertaken are shedding light on the roots of these disorders. (21)A Researchers have also uncovered previously unidentified networks of genes and the buriedelements, which might contribute to the chances of developing such disorders. “We’re not claiming inthe remotest way to have figured out the underlying mechanism of these diseases, or how you would goabout designing drugs, but we are highlighting genes, pathways and also cell types that are associatedwith these diseases,” says Mark Gerstein, a molecular biophysicist at Yale University in New Haven,Connecticut. (22)E Unlike disorders caused by mutations in a single gene — such as cystic fibrosisor some types of muscular dystrophy — neuropsychiatric disorders including schizophrenia involvehundreds of genes that interact with environmental factors. (23)B Over the past decade, scientistshave identified numerous genetic variants that are associated with such disorders. But in many cases, it isnot clear how the sequence changes alter gene function — if at all. “Typically, when we do a geneticstudy, we might find 50 associated genetic variants all clustered in the same region of the genome, andmaybe only one of them is directly influencing the risk of disease,” says Michael O’Donovan, apsychiatric geneticist at Cardiff University, UK. Further complicating matters, some of these variants fallin regions of DNA that do not code for proteins. (24)C But buried within them are the codes forelements that regulate gene expression, such as transcription factors and microRNAs, which can alsohave a powerful influence on a person’s disease risk.
(A)Among the discoveries are elements buried in the genome’s ‘dark matter’ that seem to regulate geneexpression.
(B) Each gene contributes only a small amount to the overall disease risk.
(C) Until the past few years, scientists presumed these areas to be wastelands.
(D)Pinpointing how gene variants contribute to disease, however, has been a major challenge.
(E) He was involved in a number of the project’s studies, selection of which were published this weekin Science.
20
(A)Among the discoveries are elements buried in the genome’s ‘dark matter’ that seem to regulate geneexpression.
(B) Each gene contributes only a small amount to the overall disease risk.
(C) Until the past few years, scientists presumed these areas to be wastelands.
(D)Pinpointing how gene variants contribute to disease, however, has been a major challenge.
(E) He was involved in a number of the project’s studies, selection of which were published this weekin Science.

參考答案

答案：D
難度：適中0.666667
統計：A(1),B(1),C(2),D(8),E(0)

內容推薦

內容推薦