Chromosome-wide distribution of haplotype blocks and the role of recombination hot spots.

Recent studies of human populations suggest that the genome consists of chromosome segments that are ancestrally conserved ('haplotype blocks'; refs. 1-3) and have discrete boundaries defined by recombination hot spots. Using publicly available genetic markers, we have constructed a first-generation haplotype map of chromosome 19. As expected for this marker density, approximately one-third of the chromosome is encompassed within haplotype blocks. Evolutionary modeling of the data indicates that recombination hot spots are not required to explain most of the observed blocks, providing that marker ascertainment and the observed marker spacing are considered. In contrast, several long blocks are inconsistent with our evolutionary models, and different mechanisms could explain their origins.

Assessment of symptoms in adult survivors of incest: a factor analytic study of the Responses to Childhood Incest Questionnaire.

Although research has established the long-term damaging effects of incest, these efforts have suffered from the lack of valid, standardized assessment instruments. The present study reports on the construction and factor validation of the Response to Childhood Incest Questionnaire (RCIQ), a self-report instrument that assesses a range of commonly reported symptoms experienced by adult survivors of incest. A clinical population of 104 adult women who had experienced childhood or adolescent incest completed the RCIQ. A factor analysis of the RCIQ items revealed seven factors which corresponded to hypothesized stress response themes experienced by survivors of traumatic events. These factors include vulnerability and isolation, fear and anxiety, anger and betrayal, reaction to the abuser, sadness and loss, and powerlessness. In addition, four factors corresponded to the diagnostic criteria for post-traumatic stress disorder: intrusive thoughts, avoidance and intrusive emotions, detachment, and emotional control and numbness. The usefulness of the RCIQ as a pre- and post-treatment measure and the need for further research is discussed.

Intrafamilial sexual abuse: family-of-origin and family-of-procreation characteristics of female adult victims.

We examined connections between incest victims' family-of-origin and family-of-procreation characteristics in a sample of 40 American women who were in treatment for childhood or adolescent experiences of victimization. Retrospective data on their families-of-origin were collected along with their perceptions of current relationships with family members in the three-generational system. Results showed a close association between family-of-origin and family-of-procreation characteristics, especially in the areas of intergenerational intimacy, intergenerational fusion/individuation, and personal authority. A number of significant correlations were also found between subjects' past and present relationships with family-of-origin members and the dimensions of moral and religious orientation, achievement, and intellectual and cultural orientation, conflict, and control in their family-of-procreation. Some aspects of individual adjustment, including alienation, emotional discomfort, and defensiveness, were strongly related to various family-of-origin and family-of-procreation characteristics.

Mining SNPs from EST databases.

There is considerable interest in the discovery and characterization of single nucleotide polymorphisms (SNPs) to enable the analysis of the potential relationships between human genotype and phenotype. Here we present a strategy that permits the rapid discovery of SNPs from publicly available expressed sequence tag (EST) databases. From a set of ESTs derived from 19 different cDNA libraries, we assembled 300,000 distinct sequences and identified 850 mismatches from contiguous EST data sets (candidate SNP sites), without de novo sequencing. Through a polymerase-mediated, single-base, primer extension technique, Genetic Bit Analysis (GBA), we confirmed the presence of a subset of these candidate SNP sites and have estimated the allele frequencies in three human populations with different ethnic origins. Altogether, our approach provides a basis for rapid and efficient regional and genome-wide SNP discovery using data assembled from sequences from different libraries of cDNAs.