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Biology subjects

Sy, M.

Publications and source records attributed to Sy, M..

5 recordsLinked to original sources

Continuous Integration and Software Quality in Scientific Software: A Large-Scale Empirical Analysis of GitHub Repositories

Bioinformatics software plays a central role in biological research, yet many academic projects lack robust testing and continuous integration (CI) practices. This absence can compromise reproducibility, accessibility, and long-term maintainability. In this study, we conduct an empirical analysis of GitHub repositories spanning bioinformatics and other scientific software domains to examine the relationship between CI, software testing, and software quality. Repository discovery was performed using domain-specific search terms via GitHub's Application Programming Interface (API). This was followed by a layered data extraction pipeline, which included a Large Language Model (LLM) validation step, that connected repositories to published works, institutions, authors, funding, and citation counts. By integrating repository activity, community engagement, and backlog health into a composite Repository Quality Index (RQI), we find that the presence of CI and software tests is significantly associated with higher repository quality. Additionally, repositories with higher academic citation counts tend to cluster in higher RQI tiers, suggesting that software quality, which is driven by proper testing and integration, is associated with academic impact and funding status. These results demonstrate that adopting industry-standard development practices, such as CI and software testing, is a tractable path toward more sustainable and impactful academic software and funding opportunities.

bioinformatics↗

Myelin pathology is a key feature of X-linked Dystonia Parkinsonism

X-linked Dystonia-Parkinsonism (XDP) is a progressive, adult-onset neurodegenerative movement disorder that predominantly affects males of Filipino descent1-3. The disease is caused by the insertion of a SINE-VNTR-Alu subfamily F (SVA_F) retrotransposon within an intron of the TATA-box binding protein-associated factor 1 (TAF1) gene4. A major barrier to understanding the pathophysiology of XDP has been the lack of relevant animal models. Here, we introduce a novel conditional humanized XDP mouse model harboring a hybrid mouse-human Taf1/TAF1 gene (hyTAF1) containing the pathogenic SVA_F insertion. We activated the hyTAF1 in Nestin+ neural progenitor cells and found that the resulting XDP male mice recapitulate features of the human disease including severe motor impairment, striatal atrophy, and reactive gliosis. Transcriptomic, histological, and electron microscopy analysis revealed a dramatic reduction in oligodendrocyte lineage cells and widespread myelin disruption. Consistent with these findings, postmortem brain tissue from XDP patients revealed similar myelin pathology, including near-complete loss of myelin in parts of the medial prefrontal cortex. Together, these results identify oligodendrocyte dysfunction and myelin loss as previously unrecognized contributors to XDP pathogenesis, providing new mechanistic insight into this debilitating disorder.

neuroscience↗

MSH3 is a genetic modifier of somatic repeat instability in X-linked dystonia parkinsonism

X-linked dystonia parkinsonism (XDP) is a progressive adult-onset neurogenerative disorder caused by the insertion of a SINE-VNTR-Alu (SVA) retrotransposon in TAF1 gene. One element of the SVA is a tandem polymorphic CCCTCT repeat tract whose length inversely correlates with the age of disease onset. Previous observations that the repeat exhibits length-dependent somatic expansion and that XDP onset is modified by variation in DNA repair gene MSH3 indicated that somatic repeat expansion is an important disease driver. Here, we sought to uncover genetic modifiers of CCCTCT instability in XDP patients and to provide a mechanistic link between somatic instability and disease. We determined quantitative metrics of both repeat expansion and repeat contraction in blood. Using genetic association analyses of exome sequencing data, as well as directed sequencing of a variant MSH3 repeat, we found that MSH3 modifies repeat expansion and contraction in blood as well as age at onset. MSH3 alleles associated with earlier disease onset were associated with more expansion and less contraction. Conversely, alleles associated with later disease onset were associated with less expansion and more contraction. Notably, MSH3 repeat alleles were also similarly associated with expansion and contraction in brain tissues. Our findings provide key evidence that MSH3s role(s) in CCCTCT repeat dynamics underlies its impact on clinical disease and indicate that therapeutic strategies to lower or inhibit MSH3 are predicted to both slow CCCTCT expansion and promote CCCTCT contraction, impacting the disease course prior to clinical onset.

genetics↗

High-throughput profiling of natural acquired humoral immune response to a large panel of known and novel full length ectodomain P. falciparum merozoite vaccine candidates under reduced malaria transmission.

Despite recent progress in the fight against malaria, it still remains a global health challenge necessitating development of intervention strategies. However, the search for malaria vaccine(s) has so far been very challenging. Multiple targets have been tested and so far only a few show promise with one having been endorsed by the WHO. In this study we explore the development of immunity in a low transmission setting, with very few documented re-infections, in order to understand the kinetics of the development and waning of immunity to current and novel blood-stage vaccine candidate antigens. To do this we performed a high-throughput measurement of natural acquired immunity against P. falciparum antigens utilizing a well-established micro-array platform based on the mammalian protein expression system. This large panel of known and novel recombinant full length ectodomain P. falciparum merozoite vaccine candidates were differently recognized by the immune system. Based on the overal spread of the data, some of these antigens induced the acquisition of high levels (1st tertile) of antibodies, among which included novel antigens such as PF3D7_1025300, PF3D7_1105800, PF3D7_1334400, PF3D7_0911300, PF3D7_1252300, PF3D7_1460600, PF3D7_1453100, PF3D7_0831400 and some induced low levels of antibodies (3rd tertile) while others induced moderate levels (4th tertile). In this longitudinal cohort with low level of malaria endemicity, acquisition of humoral immunity to these full length ectodomains P. falciparum antigens demonstrate different dynamics over-time, whereby it was either not acquired or if it was acquired it was either maintained or lost at different rates. These various identified novel antigens are potentially ideal candidates to be prioritized for further functional and or serological studies.

immunology↗

Plasmodium falciparum population genetic complexity influences transcriptional profile and immune recognition of highly related genotypic clusters

As transmission intensity has declined in Senegal, so has the genetic complexity of circulating Plasmodium falciparum parasites, resulting in specific genotypes emerging and persisting over years. We address whether changes in parasite genetic signatures can alter the immune repertoire to variant surface antigens, and whether such responses can influence the expansion or contraction of specific parasite genotypes in the population. We characterize parasites within genotypic clusters, defined as identical by a 24-SNP molecular barcode and a haplotype identifier for other highly polymorphic loci; we measure expression of variant surface antigens (VSA) such as PfEMP-1 by transcript expression typing and expressed var DBL1 sequencing in ex vivo and short-term adapted RNA samples; and we measure IgG responses against VSAs from short-term adapted parasites. We find that parasites within genotypic clusters are genetically identical at other highly polymorphic loci. These parasites express similar Ups var classes and largely the same dominant var DBL1 sequences ex vivo. These parasites are recognized similarly by anti-VSA antibodies after short-term adaptation to culture; however, antibody responses do not correlate with genotype frequencies over time. Both genotype-specific and multiple genotype-reactive surface IgG responses are observed in this population. Parasites with identical genomes are extremely similar in their expression and host antibody recognition of VSAs. Monitoring changes in population-level parasite genomics and transmission dynamics is critical, as fluctuations will influence the breadth of resulting host immune responses to circulating parasite genotypes. These findings suggest shared immune recognition of genetically similar parasites, which has implications for both our understanding of immunity and vaccine development strategies in malaria elimination settings.

microbiology↗