In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Context: Pandemic strains of HIV-1 (group M) encode a total of nine structural (gag, pol, env), regulatory (rev, tat) and accessory (vif, vpr, vpu, nef) genes. However, some subtype A and C viruses exhibit an unusual gene arrangement in which the first exon of rev (rev1) and the vpu gene are placed in the same open reading frame. Although this rev1-vpu gene fusion is present in a considerable fraction of HIV-1 strains, its functional significance is unknown.', 'Examining infectious molecular clones (IMCs) of HIV-1 that encode the rev1-vpu polymorphism, we show that a fusion protein is expressed in infected cells. Due to the splicing pattern of viral mRNA, however, these same IMCs also express a regular Vpu protein, which is produced at much higher levels. To investigate the function of the fusion gene, we characterized isogenic IMC pairs differing only in their ability to express a Rev1-Vpu protein. Analysis in transfected HEK293T and infected CD4+ T cells showed that all of these viruses were equally active in known Vpu functions, such as down-modulation of CD4 or counteraction of tetherin. Furthermore, the polymorphism did not affect Vpu-mediated inhibition of NF-кB activation or Rev-dependent nuclear export of incompletely spliced viral mRNAs. There was also no evidence for enhanced replication of Rev1-Vpu expressing viruses in primary PBMCs or ex vivo infected human lymphoid tissues. Finally, the frequency of HIV-1 quasispecies members that encoded a rev1-vpu fusion gene did not change in HIV-1 infected individuals over time.\Question: Does a Naturally Occurring rev1-vpu Fusion Gene Confer a Fitness Advantage to HIV-1?
Expression of a rev1-vpu fusion gene does not affect regular Rev and Vpu functions or alter HIV-1 replication in primary target cells. Since there is no evidence for increased replication fitness of rev1-vpu encoding viruses, this polymorphism likely emerged in the context of other mutations within and/or outside the rev1-vpu intergenic region, and may have a neutral phenotype.

Context: rs1333049 polymorphism on chromosome 9p21 has been shown to affect susceptibility to coronary artery disease (CAD) in Caucasians. This study examined the association of rs1333049 with myocardial infarction (MI), angiographic severity of CAD and clinical outcome after a first acute MI in Han Chinese.', 'rs1333049 polymorphism was genotyped in 520 patients with a first acute MI and in 560 controls. The number of angiographically documented diseased coronary arteries (luminal diameter stenosis > or = 50%), echocardiographic left ventricular ejection fraction (LVEF), and major adverse cardiac events (MACE) during follow-up (mean, 29+/-15 months) were recorded.', 'Patients with MI had higher frequencies of the CC genotype (30.0% vs. 20.7%) or C allele (55.5% vs. 46.2%) compared with controls (all p<0.01). rs1333049 polymorphism was strongly associated with MI [odds ratio (OR) 1.48, 95% confidence interval (CI) 1.22-1.79] after adjusting for traditional risk factors. Although longer hospitalization stay was observed in patients with the rs1333049-C allele, this polymorphism was not related to angiographic severity of CAD, LVEF, and occurrence of MACE after MI.\Question: Is chromosome 9p21 polymorphism associated with myocardial infarction but not with clinical outcome in Han Chinese?
This study demonstrates an association of rs1333049 polymorphism locus on chromosome 9p21 with risk for MI, but not with post-MI prognosis in Han Chinese.

Context: To determine the nature and extent of undersupply and the economic consequences of oversupply of medication among non-adherent patients.', 'This study used copies of repeat prescriptions (= multiple dispensations), collected during 1 week in 2002 at 16 Swedish community pharmacies. For patients with a refill adherence below 80%, treatment gaps were defined as the number of days they had no drug available. The cost of drug oversupply (i.e., refill adherence > 120%) was calculated from the prices of the drug packages dispensed.', 'The number of collected repeat prescriptions was 3,636. The median of treatment gaps among patients with a refill adherence below 80% was 53 days per 90-100 days treatment period and the corresponding median for oversupply was 40 days. The cost of oversupply for exempt patients (i.e., patients who have paid 1,800 SEK (Euro 196; US$ 243) per year for medicines) was 32,000 SEK (Euro 3,500; US$ 4,300) higher than for non-exempt patients. An extrapolation to all Sweden indicates that exemption from charges leads to an additional oversupply of about 142 million SEK (Euro 15 million; US$ 19 million) per year above that of non-exempt patients.\Question: Does refill non-adherence to repeat prescriptions lead to treatment gaps or to high extra costs?

Both undersupply and oversupply of prescribed medicines are common in Sweden. Patients with a refill adherence below 80% seem to have less than half of the prescribed treatment available. Oversupply or drug stockpiling occurs more frequently among exempt than among non-exempt patients, and this oversupply leads to high unnecessary costs.