Genetic markers in human bone: I. Deoxyribonucleic acid (DNA) analysis.

Deoxyribonucleic acid (DNA) was isolated from a number of spongy and compact human bone tissue specimens, and the yield was estimated on a "per milligram of starting tissue" basis. DNA was, in addition, isolated from a number of corresponding blood and bone tissue specimens. Spectrophotofluorometry and ethidium bromide visualization on minigels were used to estimate the quantity and degree of degradation of DNA. The DNA from several blood-bone pairs is shown to give concordant restriction fragment length polymorphism (RFLP) typing results by two different typing protocols with five different single-locus probes. DNA from several additional blood-bone pairs is shown to give concordant results for human leucocyte antigen (HLA)-DQ alpha phenotypes following polymerase chain reaction (PCR) amplification and hybridization to specific allele-specific oligonucleotide (ASO) probes, and for the variable numbers of tandem repeats (VNTR) length polymorphisms 3' to the human apolipoprotein B (APOB) gene following PCR amplification with specific primers and analysis of the products by electrophoresis and ethidium bromide visualization.     

Who's the Boss? Patterns of Perceived Control in Adolescents' Friendships

This study examined the nature and correlates of different patterns of perceived control in adolescents' relationships with their best friends. Participants included firstborn adolescents (M = 14.94 years), their younger siblings (M = 12.44 years) and both their mothers and fathers in 163 families as well as a best friend of each adolescent (M = 15 years). Data were collected from family members during home visits regarding adolescents' family relationships, friendships, and psychosocial adjustment; time use data were gathered during a series of 7 nightly phone interviews. Information was obtained from best friends during a brief phone interview. We developed a typology of 3 different patterns of perceived friendship control based on the combination of adolescents' and their best friends' ratings of relational control. Patterns of control in adolescents' friendships were associated with the distribution of control in both parents' marriages and adolescents' sibling relationships. Further analyses, designed to test developmental predictions, revealed connections between friendship control and other qualities of adolescents' friendships (i.e., intimacy, conflict, perspective-taking).     

Institutional Change and Ethnic Parties in South America

The central question of this article is why indigenous social movements formed electorally viable political parties in Latin America in the 1990s. This development represents a new phenomenon in Latin America, where ethnic parties have been both rare and unpopular among voters. Institutional reforms in six South American countries are examined to see if the creation and success of these parties can be correlated with changes in electoral systems, political party registration requirements, or the administrative structure of the state. The study concludes that institutional change is likely to be a necessary but not sufficient condition for the emergence and electoral viability of ethnic parties.