Family History Of Type 2 Diabetes: A Population-based Screening Tool For Prevention?
Family history of type 2 diabetes: A population-based screening tool for prevention? Purpose: To evaluate the use of self-reported family medical history as a potential screening tool to identify people at-risk for diabetes. Methods: The HealthStyles 2004 mail survey comprises 4345 US adults who completed a questionnaire to ascertain personal and family history of diabetes, perceived risk of diabetes, and practice of risk-reducing behaviors. Using number and type of affected relatives, respondents were ranked into three familial risk levels. Adjusted odds ratios (AORs) were obtained to evaluate associations between familial risk and prevalent diabetes, perceived risk of disease, and risk-reducing behaviors. Validity of family history as a screening tool was examined by calculating sensitivity, specificity, and positive and negative predictive values. Results: Compared to those of average risk, people with moderate and high familial risk of diabetes were more likely to report a diagnosis of diabetes (AOR: 3.6, 95% CI: 2.8, 4.7; OR: 7.6, 95% CI: 5.9, 9.8, respectively), a higher perceived risk of diabetes (AOR: 4.6, 95% CI: 3.7, 5.7; OR: 8.5, 95% CI: 6.6, 17.7, respectively), and making lifestyle changes to prevent diabetes (AOR: 2.2, 95% CI: 1.8, 2.7; OR: 4.5, 95% CI: 3.6, 5.6, respectively). A positive familial risk of diabetes identified 73% of all respondents with diabetes and correctly predicted prevalent diabetes in 21.5% of respondents. Conclusion: Family history of diabetes is not only a risk factor for the disease but is also positively associated with risk awareness and risk-reducing behaviors. It may provide a useful screening tool for detection and prevention of diabetes. Type 2 diabetes accounts for 90%95% of all cases of diabetes 1 and is a classic example Continue reading >>
Genetics And Type 1 Diabetes
If you have type 1 diabetes, you might wonder if your child would get it, too. Or if one of your parents has it, what it means for you. Your genes definitely play a role in type 1, a less common form of diabetes that’s often diagnosed in children and young adults. But they’re not the whole story. Like much in life, it’s a mix of nature and nurture. Your environment, from where you grow up to the foods you eat, also matters. Researchers don’t know exactly how -- and how much -- all those things affect your chances of getting the disease. Your genes set the stage, but you can’t be certain how it'll all play out. There’s no diabetes gene that gets turned on or off to give you type 1. Instead, a bunch of them play a role, including a dozen or so that have the biggest say: the HLA genes. They make proteins your immune system uses to keep you healthy. Since type 1 diabetes is an autoimmune disease -- your body destroys the cells that make insulin -- it makes sense that HLA genes are front and center. There are thousands of versions of them in the human gene pool. Which ones you get from your parents affect your chances of diabetes in a big way. Some make you more likely to get it, while others can help protect you from it. You have type 1 if your body makes little or no insulin, a hormone that helps your body turn sugar into energy. Certain genes are more common in one group of people than in another. That’s why race and ethnicity affect things, too. For example, white people are more likely to have type 1 diabetes than others. But even if you have genes that make you more likely to get type 1, that doesn’t mean you definitely will. Even with identical twins -- who have the same exact genes -- sometimes one gets it and the other doesn’t. That’s where the e Continue reading >>
Genetics Of Type 1 Diabetes
Abstract BACKGROUND: Type 1 diabetes, a multifactorial disease with a strong genetic component, is caused by the autoimmune destruction of pancreatic β cells. The major susceptibility locus maps to the HLA class II genes at 6p21, although more than 40 non-HLA susceptibility gene markers have been confirmed. CONTENT: Although HLA class II alleles account for up to 30%–50% of genetic type 1 diabetes risk, multiple non-MHC loci contribute to disease risk with smaller effects. These include the insulin, PTPN22, CTLA4, IL2RA, IFIH1, and other recently discovered loci. Genomewide association studies performed with high-density single-nucleotide–polymorphism genotyping platforms have provided evidence for a number of novel loci, although fine mapping and characterization of these new regions remain to be performed. Children born with the high-risk genotype HLADR3/4-DQ8 comprise almost 50% of children who develop antiislet autoimmunity by the age of 5 years. Genetic risk for type 1 diabetes can be further stratified by selection of children with susceptible genotypes at other diabetes genes, by selection of children with a multiple family history of diabetes, and/or by selection of relatives that are HLA identical to the proband. SUMMARY: Children with the HLA-risk genotypes DR3/4-DQ8 or DR4/DR4 who have a family history of type 1 diabetes have more than a 1 in 5 risk for developing islet autoantibodies during childhood, and children with the same HLA-risk genotype but no family history have approximately a 1 in 20 risk. Determining extreme genetic risk is a prerequisite for the implementation of primary prevention trials, which are now underway for relatives of individuals with type 1 diabetes. Type 1 diabetes (T1D),2 a multifactorial disease with a strong genetic compone Continue reading >>
Type 2 Diabetes
Type 2 diabetes is a disorder characterized by abnormally high blood sugar levels. In this form of diabetes, the body stops using and making insulin properly. Insulin is a hormone produced in the pancreas that helps regulate blood sugar levels. Specifically, insulin controls how much glucose (a type of sugar) is passed from the blood into cells, where it is used as an energy source. When blood sugar levels are high (such as after a meal), the pancreas releases insulin to move the excess glucose into cells, which reduces the amount of glucose in the blood. Most people who develop type 2 diabetes first have insulin resistance, a condition in which the body's cells use insulin less efficiently than normal. As insulin resistance develops, more and more insulin is needed to keep blood sugar levels in the normal range. To keep up with the increasing need, insulin-producing cells in the pancreas (called beta cells) make larger amounts of insulin. Over time, the beta cells become less able to respond to blood sugar changes, leading to an insulin shortage that prevents the body from reducing blood sugar levels effectively. Most people have some insulin resistance as they age, but inadequate exercise and excessive weight gain make it worse, greatly increasing the likelihood of developing type 2 diabetes. Type 2 diabetes can occur at any age, but it most commonly begins in middle age or later. Signs and symptoms develop slowly over years. They include frequent urination (polyuria), excessive thirst (polydipsia), fatigue, blurred vision, tingling or loss of feeling in the hands and feet (diabetic neuropathy), sores that do not heal well, and weight loss. If blood sugar levels are not controlled through medication or diet, type 2 diabetes can cause long-lasting (chronic) health prob Continue reading >>
What Causes Type 2 — Genes Or Food?
There’s a major split in the Type 2 diabetes world. Some believe Type 2 is all about diet (and maybe exercise.) Others say it’s mostly a genetic illness and that diet doesn’t make much difference. Who’s right? This disagreement came to the forefront in the controversy over TV chef Paula Deen. When Deen told the world she had Type 2 diabetes, some people blamed the high-sugar and high-fat food she cooks on her shows. (One signature dish is deep-fried cheesecake.) But Deen denied her diet had much to do with it. She pointed out that many people eat like her and don’t get diabetes. She said her genes were at fault, even though no one else in her family has diabetes. Bloggers jumped in; some to attack Deen, some to defend her. On Diabetes Self-Management, Jan Chait wrote, “Psst! Food does NOT give you diabetes!” Some doctors agreed. Dr. Terry Simpson wrote, “It is more a matter of genetics than anything else. For those who are unlucky enough to have the genetic code that predisposes them to diabetes, the odds are they will become its victim… Even the most “in shape” individual, who eats “right” who has the genetics for diabetes can no more avoid that than you can avoid a car accident if someone misses a stop sign because they are texting.” I beg to differ. Blaming genes without referencing diet makes no sense at all. There has been an increase in diabetes worldwide of 100% to 400% (depending on location) in the last 20 years. Genes don’t change that fast. The environment has changed. People are more sedentary and more stressed now. But the number one change has been the mass consumption of sugars and refined carbs. Dr. Robert Lustig at University of California San Francisco blames sugars for most of the diabetes increase. Our bodies just weren Continue reading >>
Ask Joslin: Type 1 Diagnosis, No Family History
Why did my child get type 1 diabetes when there is no family history of it? You are not alone. In fact, having someone in your family who has type 1 diabetes when you are diagnosed is the exception, rather than the rule. As Dr. Jason Gaglia , M.D., M.M.Sc. , researcher at Joslin Diabetes Center explains, “At most only 10 to 15 percent of persons with type 1 diabetes have an affected first degree relative (the majority of people diagnosed do not have a known family history of type 1 diabetes). Given that the genes are very common, why some people develop type 1 diabetes and others do not is not clear. It is hypothesized that there may be environmental factors that may play a role (viruses, certain food items, etc.) but this has not been fully answered as of yet and may be different for different individuals.” Unfortunately at present we don’t have a way to identify those at risk when they don’t have a family history. As more research is done on type 1 diabetes we may find out more about environmental triggers as well as genetics and be better able to predict who will come down with the disease. Continue reading >>
Diabetes And Family History: How Much Risk Is Genetic?
Whether you have Type I or Type II diabetes, there are several factors that could have contributed to the disease. Among these are your family’s lifestyle and your genetic history. By gaining a better understanding of these two issues, you may be able to control your diabetes with more ease, or possibly (in the case of Type II) avoid it altogether. At the very least, understanding the risks created by your genetic and family history will allow you to detect diabetes earlier and avoid the damage it can do if left untreated. How Family Affects Diabetes Risk Your family affects your diabetes risk in two different ways. First, of course, your parents contributed to your genetic heritage. But there’s also the way your parents, your siblings, and your extended family may have influenced the way you eat, exercise, and care for yourself, because these are habits you learn from the people around you as you grow up. Your genetic makeup can play a big role in both Type I and Type II diabetes, while the way a family cares for itself and the habits you’re taught in regard to diet and exercise are generally more related to Type II risk. To help prevent Type II diabetes if you don’t have the disease yet or if you’re prediabetic, there are four questions the NIDDK suggests you ask your family. These are: Does anyone in your family have Type II diabetes and if so, who are they? Has anyone in your family been told they may develop diabetes or are at risk for it? Has anyone in your family been told they need to get more exercise or lose weight in order to prevent diabetes? Did your mother have diabetes when she was pregnant, either with me or with a sibling? Type II diabetes can be greatly affected by the lifestyle a family lives. As you grow up and get older you learn a lot of Continue reading >>
The Genetics Of Diabetes
Why me? How did I deserve this? Am I to blame? These are questions that many people ask when diagnosed with a serious condition or disease. Unfortunately, there’s no clear-cut answer when it comes to diabetes. Unlike some traits, diabetes doesn’t seem to be inherited in a simple pattern, and there is a lot of misinformation out there about its causes. (Have you ever had to explain that diabetes doesn’t happen because someone ate too much sugar?) It’s apparent, though, that some people are born more likely to develop diabetes than others. We know that type 1 and type 2 diabetes have different causes, but genetics plays an important role in both types. People with diabetes inherit a predisposition to the disease, then something in their environment triggers it. Identical twins are proof that genes alone are not enough, however. Identical twins have identical genes; therefore, they should have the same genetic risk for a disease—right? Not necessarily. Research has found that if one identical twin has type 1 diabetes, the other twin will get the disease about 50 percent of the time. For type 2 diabetes, that risk rises to as much as 4 in 5. In both type 1 and type 2, identical twins have a much higher risk of both developing diabetes than non-identical (fraternal) twins, which further supports the fact that genetics is involved. So what are the causes of type 1 diabetes? Again, we know that genetics is involved. We also know that it’s not just one gene responsible, but many different genes, each of which contributes only a small part of the risk. Scientists have identified a few genes responsible for type 1, but the majority of the genetic risk is still unidentified. Because of the data about identical twins, we know that type 1 diabetes doesn’t arise solely Continue reading >>
- The Genetics of Diabetes
- DNA methylation links genetics, fetal environment, and an unhealthy lifestyle to the development of type 2 diabetes
- American Diabetes Association® Releases 2018 Standards of Medical Care in Diabetes, with Notable New Recommendations for People with Cardiovascular Disease and Diabetes
Genetics Of Type 1a
Type 1 diabetes is a complex genetic disorder. There are now at least 20 insulin-dependent genes associated with the development of diabetes. Type 1 diabetes is a complex genetic disorder. It occurs more frequently in families in which there are other relatives with type 1 diabetes and other autoimmune conditions. Children have a 5% to 6% chance of developing diabetes if their father has type 1 diabetes, and a 3% to 4% chance if their mother has type 1 diabetes. It is thought that some of the mother’s chromosomal material, or DNA, gets inactivated when passed on to the child, thereby accounting for the difference in the children’s diabetes risk. If a sibling has type 1 diabetes, the risk is 5-6%; however, if the sibling has identical MHC (Major Histocompatibility Complex) haplotypes, the risk increases. When one identical twin has diabetes, the risk of the other twin developing diabetes traditionally has been thought to be about 40%. Recent research suggests that the number may be much higher. A number of genes have been identified that are associated with the development of diabetes. The chromosomal locations of these “diabetes genes” are called inherited susceptibility loci. There are now at least 20 insulin-dependent diabetes mellitus (IDDM) susceptibility loci. The most important are: IDDM 1 (the major histocompatibility complex on chromosome 6) IDDM 2 (the insulin gene locus on chromosome 11) PTPN 22 (the protein tyrosine phosphatase gene) with a mutation at LYP (the lymphocyte-specific phosphatase gene) on chromosome 1 associated with susceptibility to multiple autoimmune disorders IDDM 1 It is estimated that about 40-50% of the risk for type 1 diabetes is associated with the MHC complex or IDDM 1 loci. The MHC genes most associated with diabetes in white Continue reading >>
Is Diabetes Genetic? Facts About Hereditary Risk
Diabetes is a complex set of diseases with no single cause. Genetic factors make some people more vulnerable to diabetes, particularly with the right environment. In addition, certain lifestyle factors can cause type 2 diabetes in individuals with no known family history. This complex interaction between genes, lifestyle, and environment points to the importance of taking steps to minimize individual diabetes risk. Is type 1 diabetes hereditary? Type 1 diabetes is an autoimmune disease, which means that it causes the body's immune system to attack healthy cells. It is often called juvenile diabetes because most people are diagnosed in childhood, and the condition then lasts their lifetime. Doctors used to think type 1 diabetes was wholly genetic. Newer studies have shown, however, that children develop type 1 diabetes 3 percent of the time if their mother has the condition, 5 percent of the time if their father has it, or 8 percent if a sibling has type 1 diabetes. Consequently, researchers now believe that something in the environment has to trigger type 1 diabetes. Some risk factors include: Cold weather. People develop type 1 diabetes in winter more frequently than summer. It is also more common in places with cool climates. Viruses. Researchers think some viruses might activate type 1 diabetes in people who are otherwise vulnerable. Measles, mumps, coxsackie B virus, and rotavirus have been linked to type 1 diabetes. Research suggests that people who develop type 1 diabetes may have autoimmune antibodies in their blood for many years before showing symptoms. As a result, the disease may develop over time, or something may have to activate the autoimmune antibodies for symptoms to appear. Is type 2 diabetes hereditary? Type 2 diabetes is the more common form of the d Continue reading >>
Genetics Of Type 2 Diabetes
Abstract BACKGROUND: Type 2 diabetes (T2D) is a complex disorder that is affected by multiple genetic and environmental factors. Extensive efforts have been made to identify the disease-affecting genes to better understand the disease pathogenesis, find new targets for clinical therapy, and allow prediction of disease. CONTENT: Our knowledge about the genes involved in disease pathogenesis has increased substantially in recent years, thanks to genomewide association studies and international collaborations joining efforts to collect the huge numbers of individuals needed to study complex diseases on a population level. We have summarized what we have learned so far about the genes that affect T2D risk and their functions. Although more than 40 loci associated with T2D or glycemic traits have been reported and reproduced, only a minor part of the genetic component of the disease has been explained, and the causative variants and affected genes are unknown for many of the loci. SUMMARY: Great advances have recently occurred in our understanding of the genetics of T2D, but much remains to be learned about the disease etiology. The genetics of T2D has so far been driven by technology, and we now hope that next-generation sequencing will provide important information on rare variants with stronger effects. Even when variants are known, however, great effort will be required to discover how they affect disease risk. Type 2 diabetes (T2D)2 is a common complex disorder with an increasing prevalence worldwide. In 2010 it was estimated that 6.6% of the world population of individuals 20–79 years old have diabetes, and that T2D constitutes approximately 90% of diabetes cases (1). This number is expected to increase epidemically as a consequence of an aging population and changes Continue reading >>
Is Type 2 Diabetes Caused By Genetics?
Diabetes is a complex condition. Several factors must come together for you to develop type 2 diabetes. For example, obesity and a sedentary lifestyle play a role. Genetics can also influence whether you’ll get this disease. If you’ve been diagnosed with type 2 diabetes, there’s a good chance that you’re not the first person with diabetes in your family. According to the American Diabetes Association, your risk of developing type 2 diabetes is: 1 in 7 if one of your parents was diagnosed before the age of 50 1 in 13 if one of your parents was diagnosed after the age of 50 1 in 2, or 50 percent, if both your parents have diabetes Several gene mutations have been linked to the development of type 2 diabetes. These gene mutations can interact with the environment and each other to further increase your risk. Type 2 diabetes is caused by both genetic and environmental factors. Scientists have linked several gene mutations to a higher diabetes risk. Not everyone who carries a mutation will get diabetes. But many people with diabetes do have one or more of these mutations. It can be difficult to separate genetic risk from environmental risk. The latter is often influenced by your family members. For example, parents with healthy eating habits are likely to pass them on to the next generation. On the other hand, genetics plays a big part in determining weight. Sometimes behaviors can’t take all the blame. Studies of twins suggest that type 2 diabetes might be linked to genetics. These studies were complicated by the environmental influences that also affect type 2 diabetes risk. To date, numerous mutations have been shown to affect type 2 diabetes risk. The contribution of each gene is generally small. However, each additional mutation you have seems to increase your Continue reading >>
Can I Get Diabetes Even If No One In The Family Has It?
Question: Can I get diabetes even if no one in the family has it? Answer: Even if no one in the family has diabetes, you can still get it. Genes don't determine for sure, whether you'll get diabetes or not; they only influence the likelihood or the susceptibility to the disease. If both of your parents have the genes that increase the risk of diabetes, you'll be at a higher risk, even if your parents or family members do not actually have the disease. In addition to genes you inherit, environmental factors play an important role, such as an unhealthy diet, or low levels of physical activity; this will increase your risk for obesity or type 2 diabetes. So, if family members eat a healthy diet and exercise, they may not have diabetes, but if you follow an unhealthy lifestyle, you might develop it. For type 1 diabetes, the environmental risk factors are a little bit less certain, but there's some data that suggest that exposure to certain viruses or possibly even toxins in the environment that may contribute to the risk of the disease. So, if none of your family members have been exposed to the environmental risk factors, none of them will develop diabetes, but if you are exposed, you may develop diabetes. Next: What Is The Current State Of Research For Genetic Testing For Diabetes? Previous: What Is The Risk That A Child Will Develop Diabetes If One Or Both Parents Are Diabetic? Continue reading >>
Genetic Abnormalities Linked To Type 2 Diabetes
RATE★★★★★ Results from genetic studies have shown that heredity (or the genetic material that we inherit through our parents and family) contributes to risk for developing both type 1 and type 2 diabetes. In type 2 diabetes, genetics plays a much stronger role than in type 1 diabetes. A person with a close relative (a child or sibling) with type 1 diabetes has a greater chance of the developing the disease than someone without such a close family history (a 5% to 6% greater risk). However, type 1 diabetes often develops in people with no family history of the disease. This suggests that factors other than genetics probably play a strong role in increasing susceptibility for the disease.1 For type 2 diabetes, your risk for developing the disease is increased if you have a close family member (parent, sibling, or child) who has type 2 diabetes or a medical condition being overweight or obese, having lipid abnormalities, or high blood pressure. In fact, a person with a first-degree relative (parent, sibling, or child) with type 2 diabetes is 5 to 10 times more likely to develop the disease than someone without family history of the disease. Additionally, the risk for developing type 2 diabetes is highest among certain ethnic groups (people of Hispanic, African, or Asian descent).2 How do genes contribute to diabetes susceptiblity? First, let’s define some terms. DNA (deoxyribonucleic acid) is the chemical structure (like a scaffold) that contains all of the genetic information used to make and maintain the body. Our DNA is made up of many individual genes (about 25,000 total). Each gene is a distinct portions of DNA that contains specific instructions for making some substance or structure that the body needs to function. Genes are packaged up in bundles called Continue reading >>
Type 2 Diabetes Causes
Type 2 diabetes has several causes: genetics and lifestyle are the most important ones. A combination of these factors can cause insulin resistance, when your body doesn’t use insulin as well as it should. Insulin resistance is the most common cause of type 2 diabetes. Genetics Play a Role in Type 2 Diabetes Type 2 diabetes can be hereditary. That doesn’t mean that if your mother or father has (or had) type 2 diabetes, you’re guaranteed to develop it; instead, it means that you have a greater chance of developing type 2. Researchers know that you can inherit a risk for type 2 diabetes, but it’s difficult to pinpoint which genes carry the risk. The medical community is hard at work trying to figure out the certain genetic mutations that lead to a risk of type 2. Lifestyle Is Very Important, Too Genes do play a role in type 2 diabetes, but lifestyle choices are also important. You can, for example, have a genetic mutation that may make you susceptible to type 2, but if you take good care of your body, you may not develop diabetes. Say that two people have the same genetic mutation. One of them eats well, watches their cholesterol, and stays physically fit, and the other is overweight (BMI greater than 25) and inactive. The person who is overweight and inactive is much more likely to develop type 2 diabetes because certain lifestyle choices greatly influence how well your body uses insulin. Lack of exercise: Physical activity has many benefits—one of them being that it can help you avoid type 2 diabetes, if you’re susceptible. Unhealthy meal planning choices: A meal plan filled with high-fat foods and lacking in fiber (which you can get from grains, vegetables, and fruits) increases the likelihood of type 2. Overweight/Obesity: Lack of exercise and unhealthy me Continue reading >>
