Predicting the Onset of AIDS Robert Arnold, Alex Cardenas, Zeb Russo LMU Biology Department 10/5/2011
Outline What causes a subject to develop AIDS from HIV and what separates AIDS from HIV? Focusing on dS/dN ratio The definition of AIDS, the subjects affected, and their similarities, ALIVE information New hypothesis involving the division of subjects into those with AIDS, trending towards AIDS, and AIDS free trending away Research comparison, proving assumptions incorrect Further comparisons between the subjects with AIDS and those without
dS/dN ratio related to AIDS development determined that low dS/dN ratios, subjects that select either for nonsynonymous mutation or not against it were the subjects to develop AIDS The subjects picked were 4, 9, 11, and 14, all with 0.0 dS/dN ratios along with subject 10 with a 0.2 and subject 1 with a 0.3
AIDS and CD4 counts CDC definition of AIDS is a CD4 count below 200 Once diagnosed, cannot be reversed Makes our first hypothesis irrelevant since all ‘rapid progressors’ drop below 200, AKA all 6 have AIDS Subjects 1, 3, 4, 10, 11, 15
Revised hypothesis separating those with AIDS from others Separated into 3 categories Those with AIDS: 1, 3, 4, 10, 11, 15 Those trending to AIDS: 7, 8, 9, 14 Those free of and trending away from AIDS: 2, 5, 6, 12, 13 New vision; which subjects developed AIDS? Began to focus on ALIVE research to go beyond Markham’s 4 year period
Development of two new questions Since we can tell who has AIDS, we would now like to determine whether there are any similar clones of the env gene across the AIDS subjects Does a median ds/dn ratio below 1.0 or lower determine whether you will get AIDS or not?
Our division of the Patients
Random clonal comparison To determine whether there were any similarities between clones of those who developed AIDS during the study and those at risk, we performed a ClustalW on a random selection of two clones from each subject
2 Clones Rooted Tree
Comparison of dS/dN Subject No. of observations CD4 Median intravisit nucleotide differences among clones Virus copy number (×103) Annual rate of CD4 T cell decline Slope of change in intravisit nucleotide differences per clone per year Slope of divergence (% nucleotides mutated from baseline consensus sequence per year) Median dS/dN AIDS Subject 4 4 1,028 0.9 6.8 −593 4.64 2.09 Subject 10 5 833 1.71 99.3 −363 3.16 1 0.2 Subject 11 753 2.27 62.2 1.11 0.32 Subject 15 707 15.16 171 −362 −2.94 0.68 0.7 Subject 3 819 1.82 302.5 −294 0.53 0.74 Subject 1 3 464 5.64 307.6 −117 5.1 1.55 0.3 At Risk Subject 7 1,072 317.6 −392 −0.79 1.35 1.3 Subject 8 7 538 1.24 209 −92 1.68 1.16 0.5 Subject 9 8 489 9.49 265 −11 1.58 1.21 Subject 14 9 523 50.9 −51 1.69 0.6 Not at Risk Subject 2 715 1.64 21.6 30 1.32 0.49 1.8 Subject 5 749 2.5 260.6 −41 0.06 1.4 Subject 6 405 2.82 321.4 52 1.92 0.82 0.4 Subject 12 6 772 2.8 44 0.62 0.13 Subject 13 671 0.87 1.7 53 0.28 3.5
Neither Assumption is correct Using the original data from the Bedrock website, we determined who actually developed AIDS over the full study 1, 3, 4, 6, 7, 8, 9, 10, 11, 14, 15 Only 2, 5, 12 and 13 avoided the progression to AIDS over the course of the study
2 Clones Rooted Tree Redux
Comparison of dS/dN Subject No. of observations CD4 Median intravisit nucleotide differences among clones Virus copy number (×103) Annual rate of CD4 T cell decline Slope of change in intravisit nucleotide differences per clone per year Slope of divergence (% nucleotides mutated from baseline consensus sequence per year) Median dS/dN AIDS Subject 4 4 1,028 0.9 6.8 −593 4.64 2.09 Subject 10 5 833 1.71 99.3 −363 3.16 1 0.2 Subject 11 753 2.27 62.2 1.11 0.32 Subject 15 707 15.16 171 −362 −2.94 0.68 0.7 Subject 3 819 1.82 302.5 −294 0.53 0.74 Subject 1 3 464 5.64 307.6 −117 5.1 1.55 0.3 At Risk Subject 7 1,072 317.6 −392 −0.79 1.35 1.3 Subject 8 7 538 1.24 209 −92 1.68 1.16 0.5 Subject 9 8 489 9.49 265 −11 1.58 1.21 Subject 14 9 523 50.9 −51 1.69 0.6 Not at Risk Subject 2 715 1.64 21.6 30 1.32 0.49 1.8 Subject 5 749 2.5 260.6 −41 0.06 1.4 Subject 6 405 2.82 321.4 52 1.92 0.82 0.4 Subject 12 6 772 2.8 44 0.62 0.13 Subject 13 671 0.87 1.7 53 0.28 3.5