CASE STUDY | A drug that sometimes works
A 30-year-old woman with β-thalassemia, a recessively inherited genetic disorder caused by absence of the hemoglobin β chain, had been treated with blood transfusions since the age of 7. However, in spite of the transfusions, her health was declining. As an alternative treatment, her physician administered 5-azacytidine to induce transcription of the fetal β hemoglobin chain to replace her missing β chain. This drug activates gene transcription by removing methyl groups from DNA. Addition of methyl groups silences genes. However, the physician expressed concern that approximately 40 percent of all human genes are normally silenced by methylation. Nevertheless, after several weeks of 5-azacytidine treatment, the patient's condition improved dramatically. Although the treatment was successful, use of this drug raises several important questions.
What criteria would you use when deciding to administer a drug such as 5-azacytidine?
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EBK ESSENTIALS OF GENETICS
- 1- You are studying lung cancer and use a microarray to compare gene expression between a lung cancer tumor and healthy adjacent lung tissue. If you label vour cancer cDNAwith red fiuorescence and your normal tissue with green, what color would you expect tumor suppressors to be:© a. GreenU D. RedOc.No color) d. Either Red or Green© e Yellow 2- You want to study histone modifications using Next Generation sequencing. What technique would allow you to do this?© a, Sanger sequencing© b. Fluorescence in situ hybl© c. RNA-SeqOld. ChIP-sed© e. Poymerase Chain Reaction 3-Gertrudae mcfuzzi is a rare (and ficticious) species of bird with colorful tail feathers. All Gertrude mcfuzzi develop 1 tail feather when they are born, and can grow additionaltall teathers during matunty depending on the alleles they inherit at a number of additive loci (T, S, and G) which form the geise/-complex. Each positive (+) allele adds one lalfeather and each negative - allele produces no additional feathers, based…arrow_forward1. a)What would happen if the aminoacyl tRNA synthetase responsible for charging alanine tRNAs also charged methionine tRNAs with alanine? b)What would happen if an individual was homozygous for mutant alleles of the gene encoding the aminoacyl tRNA synthetase responsible for charging leucine tRNAs?arrow_forward2ith the diagram provided please write the polypeptide. sequence obtained from the translation of the black allele genearrow_forward
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- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage LearningBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax