Allelic Gene Structure Variations in Anopheles gambiae Mosquitoes

Allelic gene structure variations and alternative splicing are responsible for transcript structure variations. More than 75% of human genes have structural isoforms of transcripts, but to date few studies have been conducted to verify the alternative splicing systematically.The present study used expressed sequence tags (ESTs) and EST tagged SNP patterns to examine the transcript structure variations resulting from allelic gene structure variations in the major human malaria vector, Anopheles gambiae. About 80% of 236,004 available A. gambiae ESTs were successfully aligned to A. gambiae reference genomes. More than 2,340 transcript structure variation events were detected. Because the current A. gambiae annotation is incomplete, we re-annotated the A. gambiae genome with an A. gambiae-specific gene model so that the effect of variations on gene coding could be better evaluated. A total of 15,962 genes were predicted. Among them, 3,873 were novel genes and 12,089 were previously identified genes. The gene completion rate improved from 60% to 84%. Based on EST support, 82.5% of gene structures were predicted correctly. In light of the new annotation, we found that approximately 78% of transcript structure variations were located within the coding sequence (CDS) regions, and >65% of variations in the CDS regions have the same open-reading-frame. The association between transcript structure isoforms and SNPs indicated that more than 28% of transcript structure variation events were contributed by different gene alleles in A. gambiae.We successfully expanded the A. gambiae genome annotation. We predicted and analyzed transcript structure variations in A. gambiae and found that allelic gene structure variation plays a major role in transcript diversity in this important human malaria vector

Lake Kivu Pilot Learning Site socio-economic baseline study

The Lake Kivu Learning Site (LKPLS) was established as a pilot site over three countries: Democratic Republic of Congo (DRC), Rwanda and Uganda. The LKPLS has been set to test the following hypotheses (Bekunda, et al., 2005): (i) Strong producer organizations have increased bargaining power and ability to collectively market produce and thus increase returns (income) to land and labor. (ii) Investments to sustain and maintain the natural resource base are more sustainable when they are linked to market-oriented production or when there are financial incentives for conserving natural resources and biodiversity. (iii) Increased livelihood options linked to markets including joint management for buffer zone inhabitants will decrease pressure on conservation areas and biodiversity and increase returns to land and labor. (iv) Investment in partnership arrangements that integrate research and development expertise and perspectives will achieve greater impact through scaling out islands of success. (v) Innovative information organization and sharing systems will enhance uptake of technologies and improve decision making. (vi) Strengthened local governance through improved community facilitation improves ability to influence development policy and advocate for support to local marketing and natural resource management initiatives. This study was conducted with the objective of establishing the baseline conditions of the socio-economic characteristics of the selected study sites. The baseline conditions will be used to test the stated hypotheses. This report is part of a larger study establishing the baseline conditions in the LKPLS

Assessing the downstream socioeconomic impacts of agroforestry in Kenya

Agroforestry is widely purported to improve the livelihoods of smallholder farmers, rehabilitate degraded landscapes, and enhance the provisioning of ecosystem services. Yet, evidence supporting these longer-term impacts is limited. Using a quasi-experimental impact evaluation design informed by a theory-based and mixed methods framework, we investigated selected intermediate and final outcomes of a nine-year effort led by Vi Agroforestry, a Swedish non-governmental organization (NGO), to promote agroforestry in large sections of Bungoma and Kakamega counties in western Kenya. We compared households belonging to 432 pre-existing farmer groups operating in 60 program villages and 61 matched comparison villages. To address potential self-selection bias, we used program targeting as an instrument for program participation, combined with the difference-in-differences approach to control for time-invariant differences between our treatment and comparison groups. We complemented the above with semi-structured interviews with a sub-sample of 40 purposively selected program participants. Despite evidence of variable program exposure and agroforestry uptake, we found modest, yet statistically significant, effects of Vi Agroforestry’s program on intermediate outcomes, such as agroforestry product income, fuelwood access, and milk yields among dairy farmers. We also found that this program modestly increased asset holdings, particularly among households represented by female program participants