RESUMO
Retrotransposons comprise about 45% of the human genome1, but their contributions to human trait variation and evolution are only beginning to be explored2,3. Here, we find that a sequence of SVA retrotransposon insertions in an early intron of the ASIP (agouti signaling protein) gene has probably shaped human pigmentation several times. In the UK Biobank (n = 169,641), a recent 3.3-kb SVA insertion polymorphism associated strongly with lighter skin pigmentation (0.22 [0.21-0.23] s.d.; P = 2.8 × 10-351) and increased skin cancer risk (odds ratio = 1.23 [1.18-1.27]; P = 1.3 × 10-28), appearing to underlie one of the strongest common genetic influences on these phenotypes within European populations4-6. ASIP expression in skin displayed the same association pattern, with the SVA insertion allele exhibiting 2.2-fold (1.9-2.6) increased expression. This effect had an unusual apparent mechanism: an earlier, nonpolymorphic, human-specific SVA retrotransposon 3.9 kb upstream appeared to have caused ASIP hypofunction by nonproductive splicing, which the new (polymorphic) SVA insertion largely eliminated. Extended haplotype homozygosity indicated that the insertion allele has risen to allele frequencies up to 11% in European populations over the past several thousand years. These results indicate that a sequence of retrotransposon insertions contributed to a species-wide increase, then a local decrease, of human pigmentation.
Assuntos
Proteína Agouti Sinalizadora , Retroelementos , Pigmentação da Pele , Humanos , Retroelementos/genética , Proteína Agouti Sinalizadora/genética , Pigmentação da Pele/genética , Mutagênese Insercional , Alelos , Neoplasias Cutâneas/genética , Genoma Humano , Íntrons/genéticaRESUMO
Population-scale databases have expanded to millions of protein-coding variants, yet insight into their mechanistic consequences has lagged. Here we present PROD-ATAC, a high-throughput method for discovering the effects of protein-coding variants on chromatin regulation. A pooled variant library is expressed in a disease-agnostic cell line, and single-cell assay for transposase-accessible chromatin resolves each variant's effect on the chromatin landscape. Using PROD-ATAC, we characterized the effects of more than 100 oncofusions (cancer-causing chimeric proteins) and controls and revealed that chromatin remodeling is common to fusions spanning an enormous range of fusion frequencies. Furthermore, fusion-induced dysregulation can be context agnostic, as observed mechanisms often overlapped with cancer and cell-type-specific prior knowledge. We also showed that gain-of-function activity is common among oncofusions. This work begins to outline a global map of fusion-induced chromatin alterations. We suggest that there might be convergent mechanisms among disparate oncofusions and shared modes of dysregulation among fusions present in tumors at different frequencies. PROD-ATAC is generalizable to any set of protein-coding variants.
RESUMO
Copy number variants (CNVs) are among the largest genetic variants, yet CNVs have not been effectively ascertained in most genetic association studies. Here we ascertained protein-altering CNVs from UK Biobank whole-exome sequencing data (n = 468,570) using haplotype-informed methods capable of detecting subexonic CNVs and variation within segmental duplications. Incorporating CNVs into analyses of rare variants predicted to cause gene loss of function (LOF) identified 100 associations of predicted LOF variants with 41 quantitative traits. A low-frequency partial deletion of RGL3 exon 6 conferred one of the strongest protective effects of gene LOF on hypertension risk (odds ratio = 0.86 (0.82-0.90)). Protein-coding variation in rapidly evolving gene families within segmental duplications-previously invisible to most analysis methods-generated some of the human genome's largest contributions to variation in type 2 diabetes risk, chronotype and blood cell traits. These results illustrate the potential for new genetic insights from genomic variation that has escaped large-scale analysis to date.
Assuntos
Variações do Número de Cópias de DNA , Diabetes Mellitus Tipo 2 , Humanos , Variações do Número de Cópias de DNA/genética , Diabetes Mellitus Tipo 2/genética , Fenótipo , Estudos de Associação Genética , ÉxonsRESUMO
INTRODUCTION: Enteropathy-associated T-cell lymphoma (EATL) is associated with celiac disease. With the rising prevalence of celiac disease, we hypothesized that the prevalence of EATL is also increasing. METHODS: We used the Surveillance, Epidemiology, and End Results database, which is a population-based US cancer surveillance program. We used the ICD-0-3 code 9717/3 to identify patients with EATL diagnosed between 2000 and 2020. Incidence rates were calculated using the SEER*Stat software, and annual percent change was calculated using the Joinpoint software. Log-rank tests were used to evaluate for significant difference in survival curves between groups. A Cox proportional hazards regression model was used for continuous variables and quantifying association strength of predictors. RESULTS: A total of 463 cases of EATL were identified (273 male, 190 female) with a median age of 65 (range 23-90+) years. Most of the cases were at an advanced stage at diagnosis and were treated with a combination of surgery and chemotherapy. The median survival time was 6 months. The 2000-2020 age-adjusted incidence rate per 100,000 people was 0.014, and the incidence increased between 2000 and 2020, with an annual percent change of 2.58 ( P < 0.05). Increased age at diagnosis and lack of treatment had significant impacts on survival while sex, year of diagnosis, race, and time between diagnosis and treatment had no significant impact on survival. DISCUSSION: There was a significant increase in the incidence of EATL in the United States between 2000 and 2020. Survival in this cancer remains poor and unchanged over the past 2 decades.