611 W. Union Street
Benson, AZ 85602
(520) 586-0800

LaFrontera
member support line
1-520-279-5737
M-F 5pm-8pm
24/7 weekends/holidays

AzCH Nurse Assist Line
1-866-495-6735

NAZCARE Warm Line
1-888-404-5530



SEABHS
611 W. Union Street
Benson, AZ 85602
(520) 586-0800

AzCH Nurse Assist Line
1-866-495-6735

NAZCARE Warm Line
1-888-404-5530


powered by centersite dot net

Getting Started
Here are some forms to get started. These can be printed and brought with you so that you can pre-fill out some known info ahead of time. More...


Health Sciences
Resources
Basic InformationLatest News
Deep Brain Stimulation May Slow Parkinson's, Study FindsStroke, Confusion: COVID-19 Often Impacts the Brain, Study ShowsYour Genes May Affect How You'll Heal If WoundedEven Without Concussion, Athletes' Brains Can Change After Head Jolts: StudyHealthDay In-Depth
The AI Revolution: For Patients, Promise and Challenges Ahead">HealthDay In-Depth
The AI Revolution: For Patients, Promise and Challenges Ahead
HealthDay In-Depth
The AI Revolution: Giving Docs a Diagnostic Assist">HealthDay In-Depth
The AI Revolution: Giving Docs a Diagnostic Assist
Blood Test Might Predict Worsening MSKeto Diet Might Change Your Gut in More Ways Than OneParkinson's Patient Improving After First-Ever Stem Cell TherapyKey Areas of the Brain Triggered in Recent Heart Attack SurvivorsFirst Good Evidence That Brain Hits 'Replay' While You SleepSome NFL Players May Be Misdiagnosed With Brain Disease: StudyGreenhouse Gases Bad for Your BrainTransplanted Skin Stem Cells Help Blind Mice See LightBrain Plaques Signal Alzheimer's Even Before Other Symptoms Emerge: Study'It's Like You Have a Hand Again': New Prosthetic Gets Closer to the Real ThingLosing a Spouse Could Speed Brain's DeclinePaddles Against Parkinson's: Ping Pong Might Ease SymptomsIn a First, Doctors Use Robotics to Treat Brain AneurysmSkiers Study Suggests Fitness May Stave Off Parkinson'sCRISPR Gene Editing Creates 'Designer' Immune Cells That Fight CancerGene Variant Ups Dementia Risk in Parkinson's Patients: StudyGene Variation May Protect Against Alzheimer's: StudyYoung-Onset Parkinson's May Start in the Womb, New Research SuggestsNew Gene Study Unravels Cancer's SecretsDoes Size Matter? Volume of Brain Area Not Always Tied to Memory, ThinkingGene Test Might Spot Soccer Players at High Risk for Brain TroubleSevere Deprivation in Childhood Has Lasting Impact on Brain SizeIn the Future, Could Exercise's Benefits Come in a Pill?Could Brain Scans Spot Children's Mood, Attention Problems Early?Brain Damage Changes Over Time in Boxers, MMA FightersSpecial 'Invisible' Dye Could Serve as Skin's Vaccination RecordCancer Drug Shows Promise for Parkinson's Patients'Smart' Contact Lenses Might Also Monitor Eye HealthCould Obesity Alter a Child's Brain Structure?Playing Sports Might Sharpen Your HearingAntarctic Study Shows Isolation, Monotony May Change the Human BrainCould MS Have Links to the Herpes Virus?Ultrasound Treatment Might Ease Parkinson's TremorsAnimal Study Offers Hope for Treating Traumatic Brain InjuriesA Gene Kept One Woman From Developing Alzheimer's -- Could It Help Others?Could AI Beat Radiologists at Spotting Bleeds in the Brain?Pro Soccer Players More Likely to Develop Dementia: StudyExtinct Human Species Passed on Powerful Immune System GeneScientists ID Genes Tied to Left-HandednessScientists Creating Gene Map of Human 'Microbiome'New DNA Blood Test May Help Guide Breast Cancer TreatmentFootball Head Trauma Linked Again to Long-Term Brain DamageMore 'Buyer Beware' Warnings for Unregulated Stem Cell Clinics3-D Printers Might Someday Make Replacement Hearts
Questions and AnswersLinksBook Reviews
Related Topics

Medical Disorders
Mental Disorders
Mental Health Professions

One Gene Change 2 Million Years Ago Left Humans Vulnerable to Heart Attack

HealthDay News
by By E.J. Mundell
HealthDay Reporter
Updated: Jul 29th 2019

new article illustration

MONDAY, July 29, 2019 (HealthDay News) -- As far as scientists know, humans are the only species that get heart attacks linked to clogged arteries.

Now, new research suggests that just one DNA change occurring 2 to 3 million years ago may be to blame.

The finding might give insight into how to prevent and treat the attacks, according to researchers at the University of California, San Diego (UCSD). Already, they say, the findings implicate the consumption of red meat as a factor in heart attack risk.

One heart specialist said the findings are intriguing.

"There now seems to be a plausible link between genetics, diet, inflammation and atherosclerosis [hardening of the arteries]," said Dr. James Lafferty, who wasn't involved in the study. "This may truly be the missing link."

The UCSD team noted that no other species is known to suffer heart attacks due to atherosclerosis. Even chimpanzees in captivity -- which, like humans, are often inactive, collect cholesterol in their blood and can have high blood pressure -- don't get heart attacks due to fat-clogged arteries.

So why humans? To find out, researchers led by professor of pathology Dr. Nissi Varki and professor of medicine Dr. Ajit Varki looked to a gene known as CMAH. The gene's job is to produce a sialic acid sugar molecule called Neu5Gc, which in other mammals appears to greatly reduce the likelihood of atherosclerotic changes in blood vessels.

Trouble is, CMAH doesn't function in humans -- it appears to have been "switched off" by evolution millions of years ago.

The researchers theorized that this genetic event occurred because a dangerous malarial parasite recognized -- and thrived-- in the presence of Neu5Gc. So the human genome evolved to shut down CMAH and Neu5Gc production.

However, that meant humans became more vulnerable to fatty deposits in arteries, the Varkis and colleagues reported.

To test the theory, the UCSD team compared rates of atherosclerosis in normal mice, which have a working CMAH gene, and mice genetically tweaked to have a switched-off gene.

The result: Mice without active CMAH showed a near-doubling of fatty buildup in blood vessels.

That unhealthy activity rose even higher when mice without a working CMAH gene were fed red meat, which naturally contains Neu5Gc.

According to the researchers, that finding could explain the link between diets high in red meat and an upped risk for heart disease in humans. They believe that contact with Neu5Gc could set off an immune reaction in the human body, which in turn leads to a chronic state of inflammation in blood vessels.

"When the chemical that is missing from our bodies is ingested in the form of red meat, since other animals can still produce this, it seems to create an immune reaction, since we no longer produce it," said Lafferty, who is chair of cardiology at Staten Island University Hospital in New York City.

But even folks who eschew meat can get heart attacks, the UCSD team noted.

All in all, the new findings "may help explain why even vegetarian humans without any other obvious cardiovascular risk factors are still very prone to heart attacks and strokes, while [humans'] other evolutionary relatives are not," Dr. Nissi Varki said in a university news release.

Lafferty said the research may help explain an enduring medical mystery.

"As cardiologists, we are always profoundly aware that even if all risk factors do not exist humans still have reasonable chance of developing atherosclerosis," he said.

But the study also points to new hope for patients.

"There are also some new therapies that are aimed at reducing inflammation," Lafferty said, and these treatments "have been shown to reduce cardiac events, even in patients whose risk factors have been maximally modified."

He believes research like the new study "will lead to filling our knowledge gaps and lead the way to new therapeutic interventions."

The findings were published July 22 in the Proceedings of the National Academy of Sciences.

More information

There's more on heart attack prevention at the American Heart Association.