Could Autism be More Related to Environment than We Thought?

Your child’s mental health may be more linked to his environmental wellness than previously thought, according to researchers at Stanford University. Their new study in twins, published in July’s Archives of General Psychiatry, found that environmental factors may play a larger role than shared genes in the development of autism, while a second study in the same journal discovered that one potentially important environmental trigger is taking anti-depressants during pregnancy.

 

For the first study, 192 pairs of twins from a state-wide California registry of children were identified as receiving services for developmental disabilities. The researchers examined and tested each child to confirm that at least one twin was diagnosed with an autism spectrum disorder. Of the twin pairings, 54 were identical (sharing all of the same genes) and 138 were fraternal (meaning they only shared half of their genes). Lead study author Dr. Joachim Hallmayer, an associate professor of psychiatry and behavioural science at Stanford University, said it’s not surprising that the identical twins were more likely to each have autism, since they share all the same genes, but if autism was 100% due to genetics then both siblings in each pair of identical twins would have it.

 

The researchers explained that the twins’ shared environment, be it in utero or in early life, has to play a major role in their wellbeing in this way. The researchers calculated that genes account for 37% of the risk of “classic” or severe autism and 38% of the risk of milder autism spectrum disorders. This means that environmental factors form 55% of your child’s autism risk and 58% of his risk for an autism spectrum disorder. Hallmayer admitted, ‘I was very surprised. The environmental influence is stronger than I thought. It doesn’t mean that genes don’t play a role, but they may not play as big a role as thought.’

 

Dr. Gary Goldstein, president and CEO of the Kennedy Krieger Institute in Baltimore, pointed out that the results of the study confirm how important it is for researchers to investigate autism’s environmental triggers. He commented, ‘I think everyone in the field believes that genetics are important to autism and that the environment must also be involved. But we don’t know exactly what those environmental factors are, and how those factors interact with the genes. This study gives further support that we should be looking at both genes and the environment.’

 

A second study, this time carried out by researchers from Kaiser Permanente Medical Care Programme in Northern California, found that if you take antidepressants known as selective serotonin reuptake inhibitors (SSRI) during pregnancy, your child risk of autism increases two-fold. Moreover, if you take these drugs during the early stages of your pregnancy, your child’s autism risk is three times higher than the children of mothers who don’t use the antidepressants at all.

 

However, Dr. Natalie Meirowitz, chief of the division of maternal foetal medicine at Long Island Jewish Medical Centre, advises against flushing your medications if you suffer with depression, even if you’re expecting. She explained that your wellness, and your baby’s, is at risk to the depression itself, as depressed women may self-medicate with drugs and alcohol, have a poor diet, fail to keep their prenatal appointments, and be unable to care for their baby after delivery. According to Meirowitz, ‘Pregnancy is a very emotional time for women, and we know that a woman who stops her medication needs a lot of support. The decision to stop medications has to be made very carefully with the patients’ psychiatrist, obstetrician and with their significant other. It shouldn’t be made lightly.’

Categories: antidepressants, autism, autism risk, autism spectrum, environmental factors, genes, identical twins, Research, spectrum disorder, stanford university, study

How DNA Sequencing Helps to Explain Heart Disorders

Researchers from Vanderbilt University have announced the discovery of two new genes, which are both associated with heart disorders. Both genes are involved in the coding for calmodulin, a calcium-binding signalling protein, which plays a vital role in intercellular signalling in the heart, as well as other tissues. It has been found that mutations in these genes are linked to early-onset heart rhythm disorders. The findings were published in the scientific journal Circulation, and will help identification of the causes of heart disorders, as well as the development of therapeutic approaches.

 

Many cases of heart disease, despite scientific advances, still have no genetic relation. The discovery of more genes related to heart disorders suggests an advance in the medical understanding in genetic mutations. The lead researcher, Alfred George Jr., noted that this will help the medical profession to understand the cause of and possible treatments to, unexplained heart disorders. In particular, George referenced cases of infants having repeated cardiac arrests without any family history of heart problems. This would suggest that a genetic mutation is to blame. Using advanced DNA sequencing equipment, the team of researchers scanned the protein-coding regions across the genome in these children, comparing it to their parents, in order to identify the mutations. This technique is called exome sequencing, and is valued by scientists everywhere as a powerful research tool. Out of three genes coding for calmodulin, the infants had mutations in two.

 

These specific genetic mutations negatively affected the ability for calmodulin to bind calcium. Since calmodulin interacts with a range of proteins which are essential in maintaining a regular heart rhythm, a mutation that would affect the ability of calmodulin to bind calcium will automatically have a dangerous effect on heart health. Further research could help to identify the causes of early onset arrhythmias, particularly in children, and will hopefully lead to more therapies and treatments being developed.

Categories: genes, Heart disorders, heart rhythm

Researchers Find a Way to Predict Asthma in Children

The way in which the human rhinovirus wheezing illness interacts with your child’s genes may predispose him or her to asthma. This is according to researchers at the University of Chicago, whose study has shed light on how these wellness factor interact to create the respiratory condition. Carole Ober, PhD, Blum-Riese Professor of Human Genetics at the University of Chicago, along with Minal Caliskan, PhD, reported, “For the first time, we may have a genetic marker to identify which children who develop a wheezing illness when they have a cold in the first three years of life will be diagnosed with asthma later in childhood.”

With their colleagues, Ober and Caliskan looked at followed two cohorts of children from birth to seven or eight years of age, all of whom were from families at high risk for asthma. The first group, known as the COAST cohort, contains 200 children, all of whom had at least one parent with asthma, respiratory allergies or both. The 297 Danish children in the second cohort, called COPSAC, were born to mothers whose wellbeing is affected by asthma. The researchers evaluated the children for asthma from aged six to eight years in both groups

In the COAST group, the researchers began by investigating the links between genes and asthma, finding significant associations. They discovered that just under 30% of the children who did not have the asthma-related genetic marker were still diagnosed with the disease, whereas 40% of children with one at-risk copy developed asthma and 50% with two did also. There were also far more cases of human rhinovirus-related wheezing illnesses in the children who had two copies of the asthma-related genetic variation.

There was a striking difference when the researchers combined both factors, as roughly 25% of children who had no wheezing illness from human rhinovirus developed asthma. Of the children who had wheezed in the first the years of life, but lacked the risk-related genes, 40% developed asthma, which increased to nearly 60% for those with one copy of the asthma-related allele and to 90% for those with two copies. The researchers tried to replicate this finding in the Danish cohort, and found that this link between the at-risk genotype, wheezing illness in early life and asthma diagnosis persisted, even though the overall asthma prevalence was lower.

 

Researchers Find a Way to Predict Asthma in Children

Categories: Asthma, asthma related, Children, developed asthma, genes, Genetic Marker, human rhinovirus, human rhinovirus wheezing illness, related genetic, Research, wheezing illness

Genes in Knee Cartilage Reveal Link to Osteoarthritis

Your susceptibility to osteoarthritis could all be in your genes, according to research. The degenerative joint condition is the most common form of arthritis, particularly affecting older women and also those who have suffered from a fracture or joint injury.

A team of researchers from Washington University School of Medicine, in St Louis, examined tissue removed from injured knees and concluded that genes linked to obesity and ageing could also play a role in osteoarthritis.

The tissue the researchers looked at was the meniscus, cartilage found between the shinbone and thighbone, with tissue taken from 68 people who had had surgery to repair or remove torn meniscus. It is already known that a tear in the meniscus will lead to more than 50% of individuals going on to develop arthritis.

Osteoarthritis occurs when the cartilage or tissue between bone joints thins or wears away, causing the joints to rub painfully against each other. Pain, stiffness and swelling are typical symptoms of the condition, for which there is no cure. Some sufferers eventually require replacement surgery because the joint has worn so badly.

The St Louis team wanted to explore the relationship between our genes and arthritis. They analysed 28 different genes found in the meniscus that are related to obesity and ageing, examining their activity and effect on the knee joint. During their research, they isolated abnormal activity in four ageing-related genes and one obesity-related gene in the meniscus.

They found that the ageing-related genes had a low level of activity in older patients with the obesity-related gene having a low level of activity in overweight or obese patients. Both those groups are already at risk of osteoarthritis because heavier people put more pressure on their joints while the elderly suffer from wear and tear.

Their conclusion is that this low activity in the tissue could potentially cause the meniscus not to function normally and therefore be more susceptible to osteoarthritis.

The next step for the research team is to analyse every gene in the meniscus.

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Genes in Knee Cartilage Reveal Link to Osteoarthritis

Categories: genes, knee, Osteoarthritis

Grey Areas – Are Genetics and Depression Linked?

Depression is the deep-seated disorder that very few can sit into a specific model; but in a recent study, scientists in America have attempted to understand the links between genetics and its maladies.

Depression has many causes and many symptoms – it is a despair that is rarely understood and difficult to maintain. Although it is slowly becoming public knowledge, it does not necessarily mean that depression’s roots are easily found.

Depression is said to lie within genetics; the nerve endings within the body stop reacting properly, causing a chemical balance which in turn, affects weaknesses within the brain.

Can it be so easily summarised?

Sufferers of depression would likely wish that it could be.

The multiple causes and issues that arise from depression are so varied that it is difficult to pinpoint. Some argue that it is a case of nature vs nurture, where the environment or the upbringing (war, job loss, personal issues) may have something to do with the cause, whilst others believe that it is rooted within family histories.

Thirty percent of those that take drugs to reduce the effects of depression often find that it doesn’t work, whilst others say that there are effects, but they are quite limited.

Whilst scientists attempt to understand whether or not depression is an inherited condition, there are some that believe that the causes are simply induced by emotional strain.

So where does it come from?

In scientific study, it has come to note that the mind is a very distant relation of the brain. Whilst the two are from the same source, the brain is simply a control centre, telling your body what to do and how to survive. Your basic, selfish functions reside here, letting you know when to eat, sleep, run (fight or flight) and defecate.

Your mind is the younger, rebellious black sheep.

This is where the logic and holistic areas sit. This is your memory bank, your personality, imagination and reason. It’s extensive and wonderful, the complex cousin to the brain. It is here, some theorists believe, that depression emerges from; a theory that was long-considered before the study into the possible links it may have with genes.

With the origins of depression remaining a grey area, there are some that still ask – where does it go from here?

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Grey Areas – Are Genetics and Depression Linked?

Categories: depression, genes, genetics, Mental Health