HMB265H1 Lecture Notes - Lecture 9: Product Rule, Verb, Dihybrid Cross

• School: UTSG
• Department: Human Biology
• Course: HMB265H1
• Professor: Maria Papaconstantinou

Document Summary

Chi-square test: morgan"s linkage map, sturtevant"s experiment and recombination, three-point crosses and interference. The ratios found can help build a genome map. 1:1:1:1 of all gametes in a dihybrid cross. With 500 progeny, the expected number is 125 for each category. X2 chi-square test is used to assess likelihood that deviation from expectation is due to chance. It could be due to random chance and independent assortment. Transmission of gametes is based on chance events. Deviations from 1:1:1:1 ratios can represent chance events or linkage. Ratios alone will never allow you to determine if observed data are significantly different from predicted values. The larger your sample, the closer your observed values are expected to match the predicted values. Chi-s(cid:395)ua(cid:396)e test (cid:373)easu(cid:396)es (cid:862)good(cid:374)ess of fit(cid:863) (cid:271)et(cid:449)ee(cid:374) o(cid:271)se(cid:396)(cid:448)ed a(cid:374)d expe(cid:272)ted (cid:894)p(cid:396)edi(cid:272)ted(cid:895) (cid:396)esults. Accounts for sample size, or the size of the experimental population. Null hypothesis: observed values are not different from expected. For linkage studies - no linkage is null hypothesis.