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Identical Twins Type 1 Diabetes

A Handy Guide To Ancestry And Relationship Dna Tests

A Handy Guide To Ancestry And Relationship Dna Tests

If I am a type 1 diabetic (since 25 years) - what is the probability that due to genetic transformation my child/children could be diabetics too? Is it true that type 1 diabetics are genetically inherited from ancestors or is it a combination of factors? -A curious adult from California Type 1 diabetes happens because of a combination of factors. It is partly genetic. But the environment plays a role too. We know that if one parent has Type 1 diabetes, then each child is 10 times more likely to get Type 1 diabetes too. This might sound scary, but the actual risk of getting Type 1 diabetes isn't that high. The average person has around a 1 in 200 chance of developing Type 1 diabetes. So if you have a parent with it, your chances become around 1 in 20. Or in other words, you have a 5% chance of also becoming diabetic. Now this doesn't give you a lot of information about your specific situation. That 5% is made up of a large group of people. Some have a much higher risk and some have a much lower risk. This information does tell us that genes are almost certainly involved in Type 1 diabetes. But other information tells us they aren't the whole story. One way we know this is because of identical twin studies. Identical twins have the same set of genes. So if a disease were just due to genes, when one twin has it, then the other would always have it too. But this is not the case with Type I diabetes. If one twin has it, the other twin gets it less than 50% of the time. There must be something else going on here. Most likely something from the environment needs to trigger the development of Type I diabetes. Genes make that trigger more or less likely to cause the disease. Scientists are hard at work trying to figure out what these environmental triggers are and what genes are Continue reading >>

Bond Of Brothers: Teen Researchers Tackle Type 1

Bond Of Brothers: Teen Researchers Tackle Type 1

They studied at Oxford and conducted diabetes research at Harvard and Yale, yet Jake and Michael Carrion made their greatest impact when they ventured into independent research. The brothers eventually pinpointed specific genes that likely regulate the autoimmune response that causes type 1 diabetes . Then in June 2016, the siblings graduated from high school and turned 18. Identical twins from Jericho, New York, Michael and Jake have much in common: brown hair, green eyes, traveling soccer, debate club, student government, stellar GPAs, lofty scores on college entrance exams, and an immense appetite for diabetes research. Their commitment to science has opened doors and impressed scientists at leading research centers. The level of their work is beyond their age, says Li Wen, MD, PhD, senior research scientist in internal medicine at Yale School of Medicine. Its at least graduate level, almost PhD level. Diane Mathis, PhD, professor of microbiology and immunobiology at Harvard Medical School, says: Theyre bright and knowledgeable and ask really interesting questions. High school students with their knowledge of type 1 diabetes are very rare.So rare, in fact, that a publisher of peer-reviewed medical and scientific journals asked them to review articlesan honor usually reserved for scientists with a string of credentials after their names, not teens still needing parental permission. Their passion for research was sparked by their greatest difference. Jake has had type 1 diabetes since age 4; Michael doesnt have it. At age 13, they learned that type 1 has a genetic component. They were perplexed. How can we share all of our genes and one of us have this lifelong disease and the other one be perfectly fine? Jake remembers thinking. To learn about type 1 diabetes, the br Continue reading >>

Genetics

Genetics

("What are the odds of my getting diabetes?")* If your mother has Type 1 diabetes, you have a 3% risk of developing Type 1 diabetes. If your father has Type 1 diabetes, you have a 6% risk of developing Type 1 diabetes. If both your parents have Type 1 diabetes, you have a 30% risk of developing Type 1 diabetes. If your brother or sister has Type 1 diabetes, you have a 5% risk of developing Type 1 diabetes. If your non-identical twin has Type 1 diabetes, you have a 20% risk of developing Type 1 diabetes. If your identical twin has Type 1 diabetes, you have a 35% risk of developing Type 1 diabetes.** If there is no family history of diabetes, you have a 0.2% risk of developing Type 1 diabetes (by the age of 20). If your mother or father has Type 2 diabetes, you have a 15% risk of developing Type 2 diabetes. If both your parents have Type 2 diabetes, you have a 75% risk of developing Type 2 diabetes. If your brother or sister has Type 2 diabetes, you have a 10% risk of developing Type 2 diabetes. If your non-identical twin has Type 2 diabetes, you have a 10% risk of developing Type 2 diabetes. If your identical twin has Type 2 diabetes, you have a 90% risk of developing Type 2 diabetes. *These figures are approximations. Quite different estimates of risk show up on different studies from different parts of the world. The estimates listed above are most applicable to North America. Also (and importantly), remember that at least for type 2 diabetes these risks can be substantially reduced by appropriate intervention with diet, exercise, weight control,and sometimes, with medication. **Can you think of a better illustration of the fact that type 1 diabetes is clearly a mixture of both genetic susceptibility and environmental trigger? If it was all genetic then, if your ident Continue reading >>

Which Type Of Diabetes Is More Likely To Be Inherited And Why?

Which Type Of Diabetes Is More Likely To Be Inherited And Why?

Question: Which type of diabetes is more likely to be inherited and why? Answer: Type 1 diabetes typically occurs in childhood, while type 2 diabetes usually develops in adults. However, some adults develop a form of diabetes that looks very similar to type 1 diabetes, and now with the huge increase in obesity, many children and adolescents are getting type 2 diabetes. Now, both type 1 and type 2 diabetes have a genetic component; that means of course, that they tend to run in families. However, we often regard diseases that develop in childhood as being more likely to be due to genetics. But this is not the case for diabetes, and in fact, studies show that type 2, which mostly commonly develops in adulthood, seems to have a greater genetic basis than the childhood form of type 1 diabetes. For example, as you know, identical twins share 100 percent of their genetic material; however, if one twin has type 1 diabetes, the chance of that the other twin will develop it is only 10 to 20 percent. In contrast, if one twin has type 2, or the adult form of diabetes, the other twin has up to a 90 percent chance of developing type 2 diabetes. In type 2 diabetes, we know that overeating and lack of physical activity are very important contributors. Meanwhile, for type 1 diabetes, it's more the exposure to toxins in the environment, possibly viruses, and other external factors that can increase risk to this form of diabetes. Next: What Is The Risk That A Child Will Develop Diabetes If One Or Both Parents Are Diabetic? Previous: What Are The Meanings and Significance Of These Terms Related To Diabetes: 'Beta Cells,' 'Islets,' 'Glucagon,' and 'Amylin'? Continue reading >>

Type 2 Diabetes Clues Revealed From Study Of Identical Twins

Type 2 Diabetes Clues Revealed From Study Of Identical Twins

Follow all of ScienceDaily's latest research news and top science headlines ! Type 2 diabetes clues revealed from study of identical twins By studying identical twins, researchers have identified mechanisms that could be behind the development of type 2 diabetes. This may explain cases where one identical twin develops type 2 diabetes while the other remains healthy. By studying identical twins, researchers from Lund University in Sweden have identified mechanisms that could be behind the development of type 2 diabetes. This may explain cases where one identical twin develops type 2 diabetes while the other remains healthy. The study involved 14 pairs of identical twins in Sweden and Denmark. One twin had type 2 diabetes and the other was healthy. "Twins are a good model for finding mechanisms, but the results are applicable to all," said Emma Nilsson, who carried out the study with Charlotte Ling. We know that fat tissue can release hormones and regulate metabolism in different organs in the body. The question the researchers posed was whether epigenetic changes in the DNA lead to changes in the fat tissue that in turn can lead to the development of type 2 diabetes. The researchers investigated DNA methylation at 480,000 points on the DNA and looked at how it affected the expression of the genes in the identical twins. They found that genes that are involved in inflammation were up-regulated and that genes involved in the fat and glucose metabolism were down-regulated in those who had diabetes. "This means that they are not able to process fat as well, which leads to raised levels of fat in the blood and uptake of fat by other organs instead, such as the muscles, liver or pancreas. This causes insulin resistance, which leads to type 2 diabetes," said Emma Nilsson. The Continue reading >>

Concordance For Type 1 Diabetes In Identical Twins Is Affected By Insulin Genotype.

Concordance For Type 1 Diabetes In Identical Twins Is Affected By Insulin Genotype.

Concordance for type 1 diabetes in identical twins is affected by insulin genotype. Department of Diabetes and Metabolic Medicine, St Bartholomew's and the Royal London School of Medicine and Dentistry, Queen Mary and Westfield College, University of London, UK. Monozygotic twins are usually discordant (only one twin affected) for type 1 diabetes. Discordance for disease between such twins implies a role for nongenetically determined factors but could also be influenced by a decreased load of diabetes susceptibility genes. The aim of this study was to determine whether two susceptibility genes were less prevalent in discordant twins compared with concordant twins. We studied 77 monozygotic twin pairs (INS), 40 concordant and 37 discordant, for type 1 diabetes at polymorphism of the insulin gene region on chromosome 11 p and HLA-DQBI. The disease-associated INS genotype (Hph I) was identified in 87.5% of the concordant twins but only in 59.5% (P = 0.005) of the discordant twins. Neither DQB1*0201 nor DQB1*0302 was seen in 2 of 40 (5%) concordant twins compared with 8 of 37 (22%) discordant twins (P = 0.04). No statistical differences were seen between concordant and discordant twins at individual alleles of DQB1. Combining insulin and DQ data, 5% of concordant twins compared with 32.4% of discordant twins had neither DQB1*0201/DQB1*0302 nor the high-risk Hph I INS "++" genotype (P = 0.002). We conclude that the possession of the high-risk Hph I insulin genotype increases the likelihood of identical twins being concordant for type 1 diabetes and that the "load" of both major histocompatibility complex (MHC) and non-MHC susceptibility genes has an impact on the disease penetrance of type 1 diabetes. Continue reading >>

The Genetics Of Diabetes

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 >>

Glu : T1d Exchange Studies Twins With Type 1 Diabetes

Glu : T1d Exchange Studies Twins With Type 1 Diabetes

T1D Exchange Studies Twins with Type 1 Diabetes T1D Exchange, the first program of Unitio, has recently presented data at the American Diabetes Association examining diabetes management and glycemic outcomes among twins concordant for T1D. All 64 patient participants are part of the T1D Exchange Clinic Registry, which is funded by the Helmsley Charitable Trust. Both identical (monozygotic) and fraternal (dizygotic) twins were assessed. We are fortunate to have identified 32 twin pairs participating in the T1D Exchange Clinic Registry. Due to the small sample size, definitive conclusions are not possible, however the results from this analysis support what has been previously published in this area, said Kellee Miller, MPH, at the JAEB Center for Health Research. Results showed that there was less time between diagnoses in identical twin sets than in the fraternal twin sets. Identical twins were, on average, diagnosed about one year apart from each other. The average for fraternal twins was three years, and most twins are diagnosed within four years of one another. Identical twins had slightly more similar HbA1c levels and blood glucose readings per day than their fraternal counterparts. A greater difference in the timing of diagnosis was associated with a greater difference (more than 0.5%) in HbA1c in both types of twins. Twins who have both been diagnosed with T1D provide very helpful insight into the disease and how genetics may play a factor, said Dana Ball, CEO and Co-Founder of T1D Exchange. We greatly appreciate the participation of every patient in this study. All findings would be further supported with a study that included a larger number of participants. T1D Exchange has been successfully improving patient outcomes and continues to do so by addressing vario Continue reading >>

Diabetes And Genetics

Diabetes And Genetics

Tweet Genetics play a strong role in the chances of developing both type 1 and type 2 diabetes. Other factors include environment and lifestyle. Diabetes is an increasingly common chronic condition affecting millions of people in the UK alone. Diabetes and genetic risk The risk of developing diabetes is affected by whether your parents or siblings have diabetes. The likelihood of developing type 1 diabetes or type 2 diabetes differ, as you can see below. Type 1 diabetes and genetics - average risks Mother with diabetes increases risk of diabetes by 2% Father with diabetes increases risk of diabetes by 8% Both parents with diabetes increases risk by 30% Brother or sister with diabetes increases risk by 10% Non-identical twin with diabetes increases risk by 15% Identical twin with diabetes increases risk by 40% Type 2 diabetes and genetics - average risks If either mother of father has diabetes increases risk of diabetes by 15% If both mother and father have diabetes increases risk by 75% If non-identical twin has diabetes increases risk by 10% If identical twin has diabetes increases risk by 90% Some other forms of diabetes may be directly inherited, including maturity onset diabetes in the young (MODY) and diabetes due to mitochondrial DNA mutation. However, neither type 1 or type 2 diabetes may be entirely genetically determined. Experts believe that environmental factors act as either ‘initators’ or ‘accelerators.’ Several genes are known as susceptibility genes, meaning that if an individual is carrying this gene they face greater risk of developing diabetes. Similarly, other genes provide greater immune tolerance for non-diabetics. My family have type 2 diabetes, will I get it? Type 2 diabetes is, in part, inherited. First degree relatives of individuals wit Continue reading >>

The Significance Of The Concordance Rate For Type 1 (insulin-dependent) Diabetes In Identical Twins

The Significance Of The Concordance Rate For Type 1 (insulin-dependent) Diabetes In Identical Twins

, Volume 31, Issue10 , pp 747750 | Cite as The significance of the concordance rate for Type 1 (insulin-dependent) diabetes in identical twins We studied prospectively 49 non-diabetic identical twins of recently-diagnosed Type 1 (insulin-dependent) diabetic patients for up to 24 years (median 9 years). During this time 15 developed Type 1 diabetes. Actuarial analysis indicates that by 12 years 34% of the twins will have developed Type 1 diabetes and that thereafter only another 2% will do so. Inevitable bias in ascertainment of the twins makes it likely that the true figure is less. We conclude that factors which are not genetically determined must be important in the pathogenesis of the disease. The rates of developing Type 1 diabetes in the co-twins declines sharply in the years after diagnosis of the index twin, which suggests that the initiation of the process leading to Type 1 diabetes occurs within a finite, and not a prolonged, period. Concordanceidentical twinsType 1 (insulin-dependent) diabetes Marks HH, Krall LP, White P (1971) Epidemiology and detection of Diabetes. In: Joslin EP, Root H, White P, Marble A (eds) Treatment of diabetes mellitus, 11th edn. Lea and Febinger, Philadelphia, pp 1034 Google Scholar Gottlieb MS, Root HF (1968) Diabetes mellitus in twins. Diabetes 17: 693704 Google Scholar Harvald B, Hauge M (1963) Selection in diabetes in modern society. Acta Med Scand 173: 459465 Google Scholar Barnett AH, Eff C, Leslie RDG, Pyke DA (1981) Diabetes in identical twins: a study of 200 pairs. Diabetologia 20: 8793 Google Scholar Millward BA, Welsh KI, Leslie RDG, Pyke DA, Demaine AG (1987) T cell receptor beta chain polymorphisms are associated with insulin-dependent diabetes. Clin Exp Immunol 70: 152157 Google Scholar Platz P, Jacobsen BK, Morling N, Continue reading >>

Genetics Of Diabetes

Genetics Of Diabetes

You've probably wondered how you got diabetes. You may worry that your children will get it too. Unlike some traits, diabetes does not seem to be inherited in a simple pattern. Yet clearly, some people are born more likely to get diabetes than others. Type 1 and type 2 diabetes have different causes. Yet two factors are important in both. First, you must inherit a predisposition to the disease. Second, something in your environment must trigger diabetes. Genes alone are not enough. One proof of this is identical twins. Identical twins have identical genes. Yet when one twin has type 1 diabetes, the other gets the disease at most only half the time. When one twin has type 2 diabetes, the other's risk is at most 3 in 4. In most cases of type 1 diabetes, people need to inherit risk factors from both parents. We think these factors must be more common in whites because whites have the highest rate of type 1 diabetes. Because most people who are at risk do not get diabetes, researchers want to find out what the environmental triggers are. One trigger might be related to cold weather. Type 1 diabetes develops more often in winter than summer and is more common in places with cold climates. Another trigger might be viruses. Perhaps a virus that has only mild effects on most people triggers type 1 diabetes in others. Early diet may also play a role. Type 1 diabetes is less common in people who were breastfed and in those who first ate solid foods at later ages. In many people, the development of type 1 diabetes seems to take many years. In experiments that followed relatives of people with type 1 diabetes, researchers found that most of those who later got diabetes had certain autoantibodies in their blood for years before. (Antibodies are proteins that destroy bacteria or vir Continue reading >>

Genetics Of Type 2 Diabetes

Genetics Of Type 2 Diabetes

Until recently the genetic variation and genes involved in type 2 diabetes were very poorly characterised. Traditionally genetic studies focused on the collection and characterisation of multi-generation families but type 2 diabetes occurs in older age, making the collection of affected families difficult – the parents of most patients have died and most offspring have yet to develop the condition. Furthermore the increasing prevalence of type 2 diabetes over one or two generations proves that the changing environment has a strong role to play in type 2 diabetes risk – gene frequencies do not change appreciably in 1 or 2 generations, and certainly not those that influence a disease of largely post reproductive age. Two major developments mean that we now know of 65 regions of the human genome that influence type 2 diabetes risk. First, in 2007 genome wide association studies (GWAS) became possible. These studies provided scientists with the ability to analyse 100,000s of single nucleotide variants (the simplest and most abundant type of DNA marker) in a single experiment. Second, scientists realised that they would have to work together and combine case-control studies to achieve the very large sample sizes that provided adequate statistical power to identify the subtle effects of common genetic risk factors. These developments have resulted in the latest study of 35,000 European type 2 diabetes cases and 115,000 controls.[1] History and heritability of type 2 diabetes genetics. Before trying to identify genes, geneticists tend to perform twin or family studies in attempts to quantify the relative contributions of genes (heritability) and environment. Comparing disease concordance in identical twins to same sex non-identical twins is a powerful approach. However, th Continue reading >>

What Twins Can Tell Us About The Causes Of Diabetes

What Twins Can Tell Us About The Causes Of Diabetes

Stacey Divone sees double every time she looks in the mirror. She’s the slightly older of a pair of identical twins born on Christmas Eve 1976, and when she was just 5 years old, Stacey -- just like her father -- was diagnosed with type 1 diabetes. Thirty-five years later, her genetic double is still diabetes-free. “It fascinates me that we share 100% of the same genes, developed in the exact same womb and grew up in the exact same environment, eating the exact same things, having the same father who had type 1 -- yet one of us has (T1D) and the other doesn’t," Stacey says. "The human body is a mysterious thing sometimes.” So how common is it for one identical twin to have diabetes, and the other not to? The first line of the first study I dug into to answer that question read, “Monozygotic twins are usually discordant for type 1 diabetes.” Let me translate that into English for you: When it comes to identical twins, usually only one gets diabetes. How many sets of twins both have diabetes? About a third, according to the literature. If your identical twin (should you have one) has type 1 diabetes, your risk for developing type 1 yourself is “only” 35%. That's still a pretty high risk -- and there plenty of stories about twins sharing diabetes, like Amylia Grace Yeaman and her sister in Iowa, Ashley and Emily in Pennsylvania, and the Tale of Two Twins in Massachusetts -- but it’s by no means a slam-dunk, and two-thirds of sets of identical twins have a D-sibling and a sugar-normal sibling. Despite the scientific knowledge that type 1 is basically genetic, diabetes researchers have long known that identical twins don’t have the identical risk of developing type 1 diabetes; and this fact has long fueled theories of environmental causes as the root sour Continue reading >>

Genetics Of Type 1 Diabetes

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 >>

Voice Of The Diabetic

Voice Of The Diabetic

There are possible genetic components to type 1 diabetes, and we don't know what they are. There are possible environmental components, too; questions about where type 1 diabetes comes from. We need answers. Maybe you can help? The University of Minnesota is conducting a study of identical twins and diabetes. They are looking for 20 pairs of identical twins, at least ten years of age, in which one twin has type 1 and the other does not. If you fit this profile, you could help the researchers separate out the genetic (identical twins have the same genetic material) from the environmental (we never have exactly the same exposures and experiences). What is the difference between the one twin who develops the condition, and the other, who does not? Why does this matter? We cannot truly cure a medical condition until we know what causes it -- and we don't know what causes, what launches, type 1 diabetes. The Twins Study might reveal that the genetic material between affected and un-affected twins is identical -- in which case the cause of type 1 would have to be environmental. It could, on the other hand, show us a mutation, some sort of unexpected and unpredictable genetic modification -- one that we've missed up to now. Either way, the study will bring us closer to a cure for type 1 diabetes. If you want to be part of the Twins Study, and are a twin with type 1 diabetes, whose twin is diabetes-free (or vice versa), contact the researchers by telephone: 1-800-688-5252, extension 44688, local telephone: (612) 624-4688, or by e-mail: [email protected] You could be the one who makes the difference. Continue reading >>

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