Breaking News
February 17, 2019 - Sinks by Toilets in ICU Patient Rooms Harbor Harmful Bacteria
February 17, 2019 - Cancer cells’ plasticity makes them harder to stop
February 17, 2019 - Young cannabis users have increased risk of depression and suicidal behavior
February 17, 2019 - Tasmanian Devils Likely to Survive Cancer Scourge
February 17, 2019 - Neoadjuvant PD-1 blockade seems effective in glioblastoma
February 17, 2019 - Personal, social factors play role in enabling sustainable return to work after ill health
February 17, 2019 - Mouse studies show ‘inhibition’ theory of autism wrong
February 17, 2019 - Study shows how neuroactive steroids inhibit activity of pro-inflammatory proteins
February 17, 2019 - Use of liver grafts from older donors decreased despite better outcomes in recipients
February 17, 2019 - MUSC researchers discover new mechanism for a class of anti-cancer drugs
February 17, 2019 - HPV misconceptions are causing women to miss smear tests
February 17, 2019 - Sanofi and Regeneron Offer Praluent (alirocumab) at a New Reduced U.S. List Price
February 17, 2019 - Researchers say auditory testing can identify children for autism screening
February 17, 2019 - New method analyzes how single biological cells react to stressful situations
February 17, 2019 - WVU gynecologic oncologist investigates novel treatment for cervical and vaginal cancers
February 17, 2019 - ADHD diagnoses poorly documented
February 17, 2019 - Majority of gender minority youth do not identify with traditional sexual identity labels
February 17, 2019 - AbbVie, Teneobio enter into strategic transaction to develop potential treatment for multiple myeloma
February 17, 2019 - Lower Birth Weight May Up Risk for Psychiatric Disorders
February 17, 2019 - Scientists identify reversible molecular defect underlying rheumatoid arthritis
February 17, 2019 - Moffitt researchers shed light on how CAR T cells function mechanistically
February 16, 2019 - Female Anatomy May Play Big Role in Sperm’s Success
February 16, 2019 - BMI may mediate inverse link between fiber intake, knee OA
February 16, 2019 - Movement impairments in autism can be reversed through behavioral training
February 16, 2019 - Studies address racial disparities in postpartum period and cardiovascular health
February 16, 2019 - Scientists implicate hidden genes in the severity of autism symptoms
February 16, 2019 - Decreased deep sleep linked to early signs of Alzheimer’s disease
February 16, 2019 - Neuroscientists show how the brain responds to texture
February 16, 2019 - Gilead Announces Topline Data From Phase 3 STELLAR-4 Study of Selonsertib in Compensated Cirrhosis (F4) Due to Nonalcoholic Steatohepatitis (NASH)
February 16, 2019 - What Can I Do About Sweating? (for Teens)
February 16, 2019 - Companies navigate dementia conversations with older workers
February 16, 2019 - Newly developed stem cell technologies show promise for treating PD patients
February 16, 2019 - Collaborative material research could advance self-assembling nanomaterials
February 16, 2019 - Researchers take major step in creating technology that mimics the human brain
February 16, 2019 - Erasing memories associated with cocaine use reduces drug seeking behavior
February 16, 2019 - Artificial intelligence can accurately predict prognosis of ovarian cancer patients
February 16, 2019 - Racial disparities in cancer deaths on the decline for America
February 16, 2019 - FDA authorizes new interoperable insulin pump for children, adults with diabetes
February 16, 2019 - Coexisting Medical Conditions, Smoking Explain PTSD-CVD Link
February 16, 2019 - Skin Cancer Screening: MedlinePlus Lab Test Information
February 16, 2019 - ‘Happiness’ exercises can boost mood in those recovering from substance use disorder
February 16, 2019 - Cell manipulation could soon halt or reverse aging
February 16, 2019 - Pumped Breast Milk Falls Short of Breastfed Version
February 16, 2019 - Men’s porn habits could fuel partners’ eating disorders, study suggests
February 16, 2019 - Rapid progression of age-related diseases may result from formation of vicious cycles
February 16, 2019 - Immune checkpoint molecule protects against future development of cancer
February 16, 2019 - New method produces hydrogels that have properties similar to cells’ environment
February 16, 2019 - $4.1 million funding for heart research on Valentine’s Day
February 16, 2019 - General anesthesia in early infancy unlikely to have lasting effects on developing brains
February 16, 2019 - New breakthroughs for muscular dystrophy research
February 16, 2019 - First Opinion: Embryo editing for higher IQ is a fantasy. Embryo profiling for it is almost here
February 16, 2019 - Vapers develop cancer-related gene deregulation as cigarette smokers
February 16, 2019 - Bringing Antimicrobial Susceptibility Testing (AST) to the Community
February 16, 2019 - Decolonization protocol after hospital discharge can prevent dangerous infections
February 16, 2019 - Children with ASD more likely to face maltreatment, study finds
February 16, 2019 - Study finds genetic vulnerability to use of menthol cigarettes
February 16, 2019 - Promising drug developed to rejuvenate muscle cells
February 16, 2019 - H-RT should be the standard of care for men with low risk prostate cancer, study shows
February 16, 2019 - New technique using patients’ own modified cells could help treat Crohn’s disease
February 16, 2019 - Therapeutic endoscopy has an expanding role in the treatment of IBD
February 16, 2019 - Blood clot discovery could lead to development of better treatments for blood diseases
February 16, 2019 - Intervention can increase exclusive breastfeeding rates
February 16, 2019 - New project explores how gaming technologies can help cancer patients communicate better
February 16, 2019 - Catalyst Biosciences Presents Updated Data from Its Phase 2/3 Trial of Subcutaneous Marzeptacog Alfa (Activated) in Individuals with Hemophilia A or B with Inhibitors at the 12th Annual EAHAD Congress
February 16, 2019 - Rerouting nerves during amputation reduces phantom limb pain before it starts
February 16, 2019 - A Hormone Produced When We Exercise Might Help Fight Alzheimer’s
February 16, 2019 - Millions of British people breathe toxic air travelling to GPs
February 16, 2019 - Conformance of genetic characteristics found to be crucial for longer preservation of kidney graft
February 16, 2019 - Researchers use optogenetic tool to control, visualize receptor signals in neural cells
February 16, 2019 - New reversible antiplatelet therapy could reduce risk of blood clots, prevent cancer metastasis
February 16, 2019 - Testosterone is not the only hormone needed for penis development
February 16, 2019 - FDA Advisory Committee Recommends Approval of Spravato (esketamine) Nasal Spray for Adults with Treatment-Resistant Depression
February 15, 2019 - Heart surgery technology developed at Baptist Health debuts after years of secrecy
February 15, 2019 - Prescription Opioids Double Risk of Triggering Fatal Car Crash
February 15, 2019 - New study helps doctors better understand high blood pressure in pregnant women
February 15, 2019 - Beta wave control in Parkinson’s diseased brain could be a potential therapy
February 15, 2019 - Media representations of love may justify gender-based violence in young people
February 15, 2019 - Yoga May Help With Rheumatoid Arthritis Symptoms, Severity
February 15, 2019 - Obstructive sleep apnea linked to inflammation, organ dysfunction
February 15, 2019 - Master your mind: A challenge from WELL for Life
Genome study presents new way to track historical demographics of US populations

Genome study presents new way to track historical demographics of US populations

image_pdfDownload PDFimage_print
In the African component, we see smaller estimated pre-admixture effective sizes for Cuba (150,000) and Mexico (100,000) than for the Dominican Republic (700,000), suggesting that the African ancestors of the former two populations came from smaller sub-populations of Africa than the African ancestors of the latter two populations. In the European component we see smaller estimated pre-admixture effective sizes for Cuba (200,000), Mexico (150,000), and Nicaragua (120,000) than for the Dominican Republic (400,000). In the American ancestral component, the estimated pre-admixture effective sizes are similar between Nicaragua (400,000), Ecuador (700,000), and Mexico (600,000). Credit: Sharon R. Browning and colleagues

Sharon Browning of the University of Washington and colleagues developed a method to estimate historical effective population size, which is the number of individuals who pass on their genes to the next generation, to reveal the shifting demographic history of U.S. populations during the last several thousand years. They report their findings in a new study published May 24th, 2018 in PLOS Genetics.

Many populations in the U.S. are mixed, with ancestry from Europe, Africa, and the Americas. By looking at genome-wide data from several hundred individuals from a population, scientists can learn not only the current effective population size, but also the sizes of the ancestral populations that once contributed their genes. In the current study, researchers developed a method for estimating past effective population size and used it to analzye data from nine populations enrolled in a Latino health study, and from African-American and European-American populations in Pittsburgh and Memphis. They estimate that overall effective population sizes dropped substantially after the start of European and African immigration, reaching a minimum around 12 generations ago, but rebounded a few generations later. Researchers investigated these population size reductions, also known as bottlenecks, and found that the smallestbottleneck occurred in Puerto Rico, where the effective size at one pointfell to just one thousand people.

The differences in historical effective sizes between these populations can be useful for understanding why individual groups face different health and disease risks. They can also be useful for scientists in selecting populations that will be most useful for studies that identify the genes linked to specific diseases.

Sharon Browning adds: “Admixed populations in the Americas are like ropes constructed by braiding together several different fibers, with the fibers representing different ancestral population groups. The genetic composition of those different groups is overall very similar, but is different enough so that we can distinguish the genetic material from each ancestry group and study itsproperties, which tells us about the histories of those populations.

We found that around 100 generations ago, which is approximately severalthousand years ago, the effective sizes of the ancestral European, Africanand indigenous American populations contributing to current-day Americanpopulations were around several tens of thousands of individuals each. Wealso found clear signatures of the effects of migration and colonization,with reduced effective population sizes around 12 generations ago, which isapproximately 300 years ago.”


Explore further:
23andMe study sketches genetic portrait of the US

More information:
Browning SR, Browning BL, Daviglus ML, Durazo-Arvizu RA, Schneiderman N, Kaplan RC, et al. (2018) Ancestry-specific recent effective population size in the Americas. PLoS Genet 14(5): e1007385. doi.org/10.1371/journal.pgen.1007385

Journal reference:
PLoS Genetics

Provided by:
Public Library of Science

Tagged with:

About author

Related Articles