Detection of sequence variation in the HVII region of the human mitochondrial genome in 689 individuals using immobilized sequence-specific oligonucleotide probes

We have developed a rapid, immobilized probe-based assay for the detection of sequence variation in the hypervariable segment II (HVII) of the mitochondrial DNA (mtDNA) control region. Using a panel of 17 sequence-specific oligonucleotide (SSO) probes immobilized on nylon membrane strips, we typed 689 individuals from four population groups. The genetic diversity value for each population was calculated from the frequency data, and the frequencies of distinct "mitotypes" in each group were determined. We performed DNA sequence analysis of 129 samples to characterize the sequences associated with "blanks" (absence of probe signals) and weak probe signals. Out of 689 samples, we observed five heteroplasmic samples (excluding the variable C-stretch beginning at position 303) using the immobilized SSO probe panel. The SSO probe strips were used for the analysis of shed hairs and bloodstains from several criminal cases in Sweden, one of which is described here. We conclude that this mtDNA typing system is useful for human identification and significantly decreases casework turnaround time.     

Understanding Interaction Models: Improving Empirical Analyses

William Roberts Clark University of Michigan, Center for Political Studies, ISR 4202 Box 1248, 426 Thompson Street, Ann Arbor, MI 48106-1248 Matt Golder Florida State University, Department of Political Science, 531 Bellamy Building, Tallahassee, FL 32306-2230 e-mail: thomas.brambor{at}nyu.edu e-mail: wrclark{at}umich.edu e-mail: matt.golder{at}nyu.edu (corresponding author) Multiplicative interaction models are common in the quantitativepolitical science literature. This is so for good reason. Institutionalarguments frequently imply that the relationship between politicalinputs and outcomes varies depending on the institutional context.Models of strategic interaction typically produce conditionalhypotheses as well. Although conditional hypotheses are ubiquitousin political science and multiplicative interaction models havebeen found to capture their intuition quite well, a survey ofthe top three political science journals from 1998 to 2002 suggeststhat the execution of these models is often flawed and inferentialerrors are common. We believe that considerable progress inour understanding of the political world can occur if scholarsfollow the simple checklist of dos and don'ts for using multiplicativeinteraction models presented in this article. Only 10% of thearticles in our survey followed the checklist.