GORDIS EPIDEMIOLOGY 6TH EDITION TEST BANK COMPLETE 2023 - 2024

Changes in the trends in short periods suggest environmental factors in the causation of disease. The other options suggest genetic factors in the causation of disease. 2. Huntington disease is an autosomal dominant disease. It is characterized by the adult onset of abnormal movements, cognitive symptoms. For its type of transmission pattern (autosomal dominant) it is considered a a. complex genetic disease. b. multiple gene disease. c. environmental disease. d. vector borne. e. Mendelian disease. ANS: E Mendelian diseases are characterized for being mutations in single genes affecting either autosomal or sexual chromosomes, and being either dominant or recessive. Such information is enough to answer this question because the sentence indicates that Huntington is an autosomal dominant disease. 3. A total of 1,500 pairs of adult twins, 600 monozygotic and 900 dizygotic, were studied to estimate the concordance for a childhood cancer. In the 600 monozygotic twins, 40 of the pairs were concordant for the disease, 60 of the pairs were discordant for the disease, and neither twin had the disease in the remaining 500 pairs. In the 900 dizygotic twins, 30 of the pairs were concordant for the disease, 120 of the pairs were discordant for the disease, and neither twin had the disease in the remaining 750 pairs. What is the concordant rate, in monozygotic twins, of the disease in twin pairs with at least one affected member? a. 0.1 b. 0.4 c. 0.6 d. 0.7 e. 1.5 ANS: B The concordant rate of the disease in twin pairs with at least one affected member among monozygotic twins is 40, the number of pairs with concordant, divided by 100, 40 plus 60, the total number of pairs with at least one affected member. The concordant rate equals 0.4. 4. A total of 1,500 pairs of adult twins, 600 monozygotic and 900 dizygotic, were studied to estimate the concordance for a childhood cancer. In the 600 monozygotic twins, 40 of the pairs were concordant for the disease, 60 of the pairs were discordant for the disease, and neither twin had the disease in the remaining 500 pairs. In the 900 dizygotic twins, 30 of the pairs were concordant for the disease, 120 of the pairs were discordant for the disease, and neither twin had the disease in the remaining 750 pairs. What is the discordance rate, in dizygotic twins, of the disease in twin pairs with at least one affected member? a. 0.1 b. 0.2 c. 0.6 d. 0.8 e. 1.5 ANS: B The discordance rate of the disease in twin pairs with at least one affected member among of dizygotic twins is 30, the number of pairs with concordant, divided by 150, 30 plus 120, the total number of pairs with at least one affected member. The discordance rate equals 0.2. 5. A total of 1,500 pairs of adult twins, 600 monozygotic and 900 dizygotic, were studied to estimate the concordance for a childhood cancer. In the 600 monozygotic twins, 40 of the pairs were concordant for the disease, 60 of the pairs were discordant for the disease, and neither twin had the disease in the remaining 500 pairs. In the 900 dizygotic twins, 30 of the pairs were concordant for the disease, 120 of the pairs were discordant for the disease, and neither twin had the disease in the remaining 750 pairs. What is the most reasonable conclusion to be drawn from these data? a. Genetic factors are unimportant in the etiology of childhood cancer. b. The data suggest a potentially important genetic component. c. The incidence of childhood cancer within monozygotic twins is higher than dizygotic twins. d. The prevalence of childhood cancer within dizygotic twins is higher than monozygotic twins. e. Environmental factors are the major determinants of child food cancer. ANS: B The concordant rate of the disease in twin pairs with at least one affected member among monozygotic twins is 0.4, 40 divided by 100. And the concordant rate of the disease in twin pairs with at least one affected member among dizygotic twins is 0.2, 30 divided by 150. The concordance rate is higher in monozygotic twins than in dizygotic twins, which indicates that there is some role of genetic factors in childhood cancer. “Genetic factors are unimportant in the etiology of childhood cancer” is not correct, because data suggest that genetic factors are important in the etiology of childhood cancer. “The incidence of childhood cancer within monozygotic twins is higher than dizygotic twins” and “The prevalence of childhood cancer within dizygotic twins is higher than monozygotic twins” are not correct. Based on given information, we cannot calculate and compare the incidence rate or prevalence of childhood cancer. “Environmental factors are the major determinants of child food cancer” is not correct. It is hard to say that environmental factors ar