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Single nucleotide polymorphisms (SNPs) in DNA can result in phenotypes where the biochemical basis may not be clear due to the lack of protein structures. With the growing number of modeling and simulation software available on the internet, students can now participate in determining how small changes in genetic information impact cellular protein structure and function. We have developed a modular series of activities to engage lab or lecture students in examining the basis for common phenotypes. The activities range from basic phenotype testing/observation to DNA sequencing and simulation of protein structure and dynamics. We provide as an example study of the bitterness receptor TAS2R38 and PTC tasting, however these activities are applicable to other SNPs or genomic variants with a direct connection to an observable phenotype. These activities are modular and can be mixed to meet the student capabilities and infrastructure availability. The complete sequence of activities will demonstrate the direct connection between gene structure, protein structure and organism function.

The free radical scavenger pegorgotein does not appear to reduce the severity of head injuries but it may protect against adult respiratory distress syndrome in these patients. Pegorgotein is the technical name for polyethylene glycol-conjugated superoxide dismutase. In a study of 463 patients with a severe head injury randomly assigned to take placebo, a 10,000 Units per kilogram (kg) dose or a 20,000 U/kg dose of pegorgotein, there were no statistically significant differences in outcome between the groups. However, those who received 10,000 U/kg were less likely to develop adult respiratory distress syndrome., Objective.--To evaluate outcome of patients with severe closed head injury treated with pegorgotein, a scavenger of oxygen-derived free radicals. Design.--Randomized, parallel, placebo-controlled, third-party-blind, multicenter trial, with a blinded, multicenter follow-up protocol. Setting.--Twenty-nine centers in the United States. Patients.--A total of 463 patients with severe closed head injury and a Glasgow Coma Scale score of 8 or less after resuscitation and stabilization. Interventions.--Patients received a single intravenous dose of placebo, 10 000 U/kg of pegorgotein, or 20 000 U/kg of pegorgotein within 8 hours after injury. Outcome Measures.--The primary endpoint was the Glasgow Outcome Scale (GOS) score at 3 months after brain injury with GOS data trichotomized into good, fair, or poor outcome. Secondary efficacy endpoints included the Disability Rating Scale (DRS) and mortality. A secondary analysis was performed using GOS scores dichotomized into favorable and unfavorable outcomes. In a follow-up protocol at 6 months, GOS and DRS scores were again determined. Results.---Of 463 patients randomized, 162 received placebo; 149, pegorgotein 10 000 U/kg; and 152, pegorgotein 20 000 U/kg. Treatment groups were comparable with respect to demographic characteristics, mechanism of injury, and time to treatment. Pegorgotein was well tolerated at both dose levels. At month 3, the trichotomized analysis found no significant statistical difference in neurologic outcome between the pegorgotein and the placebo groups. Although differences were not statistically significant, there were more favorable outcomes and no increase in the number of deaths or vegetative states among the patients given pegorgotein, more subjects had good or favorable outcomes with the 10 000-U/kg dose than with the 20 000-U/kg dose or placebo, and less disability was observed with the 10 000U/kg dose than with either the 20 000-U/kg dose or placebo. No differences in mortality rate or cause of death were found between the 10000-U/kg and placebo groups at either month 3 or month 6. The only statistically significant difference between the groups was a decreased incidence of adult respiratory distress syndrome in the 10 000-U/kg group as compared with the placebo group (P Conclusions.--In this clinical trial of 463 patients with severe head injury, no statistically significant difference in neurologic outcome or mortality was observed between patients treated with pegorgotein and those receiving placebo. JAMA. 1996;276:538-543

Metastases, secondary cancers which have spread from the original tumor to other sites in the body, are the most common type of intracranial tumor. Patients with metastases in the brain have a very poor prognosis, usually surviving from three to six months despite radiation treatment. Chemotherapy seems to be ineffective. Because about half the cases of brain metastasis involve only a single tumor, it should, in principle, be possible to treat some patients surgically. Past research has been biased, however, and has failed to establish the efficacy of surgical treatment, since only patients with milder disease have been sent to surgery and the worst cases have received radiotherapy. For this reason a randomized trial was begun using patients over 18 years with evidence of only a single tumor in the brain. Between October 1985 and December 1988, 54 patients agreed to participate in the study; six were later discovered to have primary brain tumors, rather than metastases, and were eliminated from the analysis. Of the 48 actual participants, 25 were randomly assigned to the surgical group and 23 to the radiotherapy group. Analysis showed quality of life, as judged by the patients' abilities to care for themselves, to be much improved for the surgery group (independence for a median of 38 weeks) over the radiotherapy group (median independent care of 8 weeks). The surgical group had fewer recurrences of tumor and a median survival time of 54 weeks, as opposed to 23 weeks in the radiation group. Since only half of all patients with brain metastases have only one tumor, and only half of them have a tumor in a location amenable to surgery, about 25 percent of patients with metastatic brain tumors may enjoy extended survival as a result of surgery. For the remainder, radiotherapy is the only alternative. (Consumer Summary produced by Reliance Medical Information, Inc.)