Monday, April 15, 2024

How Likely Is Schizophrenia To Be Inherited

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Environment: Triggers And Influences

Research is continuing to reveal what influences a persons chances of developing schizophrenia. Some of those factors are:

  • your biological mothers health during pregnancy or complications with your birth
  • substance misuse
  • difficult social circumstances and stressful life events
  • trauma during childhood, such as abuse, neglect, parental death and bullying.

However, many people who experience these factors don’t develop schizophrenia. Were understanding more about the causes of schizophrenia all the time, but theres some way to go. What we do know is that there is no single cause.

Is Schizophrenia Inherited From Your Mother Or Father

Research long ago concluded that schizophrenia was in some ways passed down genetically. In fact, the National Institute of Mental Health found that having arelative diagnosed with schizophrenia can raise your chance of being diagnosed with schizophrenia by 10 percent. There is an unmistakable link between the hereditary genetic makeup passed down from your parents and developing schizophrenia, but which side of the family does schizophrenia come from?

What Are The Symptoms Of Schizophrenia In A Child

Behavior changes may occur slowly, over time. Or they may start suddenly. The child may slowly become more shy and withdrawn. He or she may start to talk about odd ideas or fears and start to cling more to parents.

Each childs symptoms may vary. Early warning signs are:

  • Trouble telling dreams from reality

  • Confused thinking, such as confusing TV with reality

  • Detailed and bizarre thoughts and ideas

  • Fear or belief that someone or something is going to harm him or her

  • Seeing, hearing, or feeling things that are not real, such as hearing voices

  • Ideas that seem real but are not based in reality

  • Extreme moodiness

  • Lots of anxiety or fear

  • Lack of emotional expression when speaking

  • Trouble doing schoolwork or a drop in levels of school success

  • Social withdrawal, such as having problems making and keeping friends

  • Sudden agitation and confusion

  • Disorganized behavior, such as doing private things in public. Or catatonic behavior, such as sitting and staring, as if the child cant move.

  • Odd behaviors, such as an older child acting like he or she is much younger

Children with schizophrenia have the same symptoms as adults with the condition. But more children hear voices. Children also dont tend to have delusions or formal thought problems until they are in their teens or older.

These symptoms may look like other health problems. Make sure your child sees his or her healthcare provider for a diagnosis.

Other Candidate Genes And Regions

Schizophrenia has not been convincingly associated with polymorphism in genes related to dopaminergic function, although meta-analyses have suggested a small but significant association for homozygosity at a polymorphism in DRD3 . A modest but significant association between schizophrenia and a polymorphism in the serotonin-2A receptor gene was reported in a meta-analysis . There is a number of evidence that suggested the role for glutamatergic dysfunction in the pathogenesis or pharmacology of schizophrenia . Cholecystokinin , which modulates dopaminergic neurotransmission has also been hypothesized to play a role in schizophrenia . In extensive review of the recent literature on molecular genetics of schizophrenia, Levinson found that new genome scan project, seen in the light of previous scans, provide support for schizophrenia candidate regions on chromosomes 1q, 2q, 5q, 6p, 6q, 8p,10p,13q,15q, and 22q.

Whats The Relationship Between Race And Schizophrenia

Schizophrenia and Genetic

Scientists say schizophrenia is only partially genetically determined. Environmental factors can also make someone vulnerable. Many genes have to have changes to sort of set the stage, Herlands says explaining that within a family lineage there will be family members who dont manifest the illness and others who do.

Managing Life With Schizophrenia

Schizophrenia an require longer-term treatment. It takes at least six months of symptoms to be diagnosed and treatment may be recommended after symptoms have reduced.

While your mental health issue is being treated, life continues. How can you live the best life you can with schizophrenia?

Doctors can provide medication. They can give you recreational activities and advice. But the desire to get better has to come from you

The Basic Genetics Of Schizophrenia

Schizophrenia aggregates in the families with no known familial subtypes. Twin and adoption studies have shown that this familiarity is explained predominantly by genetic factors, with estimates of genetic contribution ranging from 60 to 80%. However, these data do not follow a simple recessive or dominant pattern. If it were simple recessive, the frequency in children of two schizophrenic parents would be 100%, but is actually under 40%; if it were simple dominant, 50% of the offspring of one schizophrenic parent would be affected and each person with schizophrenia would have one ill parent . Moreover, the prevalence in offspring is too low to be consistent with the high monozygotic twin concordance rate. Thus, the genetic effect is not completely penetrant indicating that many relatives of people with schizophrenia may carry silent genetic susceptibility. Detail of the risk of illness among relatives with schizophrenia is shown in . A further complication is the epidemiological evidence that, while a high population prevalence has been maintained, the reproductive rate of people with schizophrenia is low.

Risk Of Schizophrenia If Your Parent Is Schizophrenic

The uncertainty surrounding the genetic makeup of schizophrenia is evident in the data surrounding the risks of developing schizophrenia based on a family member with the disorder. While parents and children share half of their genes, there is only a 6% chance that a child with a schizophrenic parent will develop schizophrenia. Another example is the risk of both identical twins developing schizophrenia. Identical twins basically have the same genetic makeup, yet if one of them has schizophrenia, the twin only has a .

Planning For The Future

Relapse prevention plan

A relapse is when, after you recover from an episode of psychosis, your symptoms return and you experience another episode.

A relapse prevention plan is a powerful tool for staying well and avoiding a worsening of your mental health issue. Making a plan involves:

  • identifying your triggers: what events or situations could set your symptoms off?
  • identifying your warning signs: what changes in your thinking, emotions and behaviour signal the early signs of psychosis?
  • planning responses: what will you do to cope or seek help when you experience triggers & warning signs?
  • listing support people: who will you call when you experience triggers & warning signs?

Having a relapse prevention can make you and the people who care for you feel more secure, even if you never have to use it.

You can read more about relapse prevention plans at and Here to Help.

Advance care directives

Because of the way schizophrenia affects thinking, feeling and behaviour, if your symptoms worsen at some time in the future, you may not be able to make good decisions about your care. It can also be hard for the people around you to know whats best for you when the situation is intense and confusing.

An advance care directive is your instructions for what you want to happen if you cant make your own choices, and who you authorise to make decisions for you.

Are You Affected By This

  • Samaritans provides emotional support, 24 hours a day for people who are experiencing feelings of distress or thoughts of suicide
  • Its number is 116 123 and is free to call and will not appear on a phone bill
  • Rethink Mental Illness has more than 200 mental health services and 150 support groups across England.
  • Its number is 0300 5000 927

“Mental health disorders are not about a single gene but about a collection of genes. We need to start thinking about this as a cumulative loading of genetics.”

The work at KCL is still in its early stages. But it has been found there are 108 genes with changes in people with schizophrenia. Now, nine genes have been found across those with depression, and 20 in people who have bipolar disorder. There are almost certainly many more still to find and scientists say many of these genes will be shared across the different conditions.

Making sense of my genetic legacy is important, because it allows me to break away from the feelings of inevitability that depression gives you. Is this meant to happen? Am I meant to get over this? Is this bigger than me?

“Evidence from the last few years also suggests that many mental disorders share common genetic risk factors – for instance, genetic variation associated with schizophrenia overlaps with both depression and bipolar disorder,” says Lewis.

Siblings can have very different outcomes. Twins Lucy and Jonny have a bipolar mother. Jonny has also suffered from the condition, while Lucy has not.

How Is Schizophrenia Diagnosed In A Child

A child with symptoms of schizophrenia needs a thorough medical and mental health evaluation. Talk with your child’s healthcare provider if you are concerned about symptoms your child is having. A child psychiatrist or other qualified mental health expert can diagnose schizophrenia in children and teens. He or she does a mental health evaluation to figure out how best to treat the child.

Geneticists Seek Key To Better Understanding Treatment Of Schizophrenia

My greatest fear is this brain of mine.The worst thing imaginable is to be terrified of ones own mind, the very matter that controls all that we are and all that we do and feel.

Given the large burden of schizophrenia on our society, it behooves us to gain a better understanding of this disorder so that more effective treatments can be developed. Because schizophrenia has been demonstrated to be highly heritable, researchers can use genetics to understand the causes of this disease and explore potential avenues for therapy. Thankfully, recent advances in our understanding of the human genome and rapidly decreasing costs of genetic sequencing are making genetic studies a viable route not just for schizophrenia, but any psychiatric disorder with a genetic component.

Schizophrenia Found To Actually Be These 8 Genetic Disorders

Schizophrenia and Genetic

Power of Positivity

Schizophrenia is a debilitating mental health disorder that affects more than 1% of the American population, or one in every 100 individuals between the ages of 16 to 30. Its symptoms include paranoid delusions, agitation, hallucinations, and dysfunctional thought processing. Until recently, schizophrenia was thought to be a single disease. However, scientists have found new evidence that suggests otherwise.

Why Positive And Negative Symptoms

Symptoms of schizophrenia can be referred to as positive or negative, but they dont mean good and bad.

Disordered thinking, hallucinations and delusions are called positive symptoms because they are something added to the persons normal experience. Low motivation and decreased pleasure are called negative because they take something away from a person’s experience.

What Should I Consider If I Want To Start A Family

If you have a mental illness, and youre thinking of starting a family, you could talk to a professional genetics counsellor.

Genetic counsellors work directly with patients and families. They can give specialist advice and information to people who have relatives with certain health conditions.

If you want to speak to a genetic counsellor, you will need to be referred by a doctor. So, you should speak to your GP or psychiatrist.

Current Issues And Challenge

The history of the search for genes contributing liability to schizophrenia is around a quarter of century old, but it is always dashed with nonreplication of the finding. This has been so despite consistent evidence from family, twin and adoption studies of an important genetic contribution; the heritability of schizophrenia is estimated to be approximately 80% . The reasons for the difficulty in finding genes include the complexity of the phenotype, heterogeneity and lack of biological marker. The mode of transmission is multifactorial where non-genetic determinants are also operating. As has been pointed earlier, schizophrenia does not conform to a classical Mendelian pattern of inheritance and it is now clear that most, perhaps all, cases involve the combined effects of many genes, each conferring a small increase in liability to the disorder; not due to single gene of major effects. As a consequence, a single gene does not seem to cause the disorder; thus no causal disease genes, only susceptibility genes are operating. Otherwise a consistently replicable linkage signal should have been detected. Advancement has also been hampered by the relatively small size of many studies. Not only are large sample needed to detect small effects, but even larger samples are needed to replicate positive findings

Finding Mental Health Services

There are a few different options available for clinical treatment. Your choice will depend on cost, severity of your symptoms and convenience, but not all services are available everywhere. For people in rural and remote areas, treatment options can be reduced, involve long travel, or alternatively can be delivered through telehealth services. Ask your GP for advice about the best options available for you.

What Can I Do To Reduce My Risk Of Developing A Mental Illness

Mental illness may run in families, but it doesnt mean that you or someone in your family will definitely become unwell.

If you have a family history of mental illness it can still help to take good care of your mental health. There are things you can do to look after your mental health. Below are some steps you can take.

Having a healthy diet

Eating a healthy, balanced diet is good for your mental and physical health.

Food can have a lasting effect on mental health. Your brain needs different nutrients to stay healthy and function well.

To help improve mental wellbeing, you should try to eat a balanced and varied diet.

If you are having issues maintaining a balanced diet, you can seek help from your GP.


Mindfulness is becoming more aware of your thoughts, feelings, body and world around you. Mindfulness can help improve mental wellbeing. It can also help you to notice signs of stress or anxiety and deal with them better.

The first step to mindfulness is to remind yourself to take notice of your thoughts, feelings, body and the world around you.

Other ways to practice mindfulness include picking a regular time each day where you try and be more aware of yourself and your surroundings. You could also try something new to help you notice the world around you in a new way. For example, you could try taking a new route to work.

Getting regular exercise

You can find more information about Mental Illness and being active by clicking .

Getting enough sleep


Current Methods For Genetic Analysis Of Complex Disorder

Available methods generally rely on the analysis of DNA markers in subject to determine whether the distribution of marker alleles in some way predicts the presence of disease. Some studies consider DNA variations within or near candidate gene. Many groups are now examining maps of the DNA markers throughout the genome to identify chromosomal regions likely to contain loci that have a major influence on susceptibility. These studies rely on the phenomenon of linkage, as exemplified by the fact that when ill parent transmits a disease-causing allele to children, numerous alleles at nearby loci are also transmitted because no recombination event has occurred in the region .

Genetic Vs Environmental Factors

Although research has found a significant genetic risk factor to schizophrenia, it is not currently possible to make predictions based on genetics as to who will ultimately develop schizophrenia.

Genome-wide association studies explain a minority of schizophrenia occurrences. Many researchers believe that gene-environment interaction has a significant role in schizophrenia development.

In other words, a person may be predisposed to develop schizophrenia due to their genes, but wouldn’t necessarily develop the condition without the additional input from environmental risk factors.

Environmental factors that have been shown to increase schizophrenia risk include:

  • Pregnancy and birth complications

When Should I Call My Childs Healthcare Provider


  • Feels extreme depression, fear, anxiety, or anger toward him or herself or others

  • Feels out of control

  • Hears voices that others dont hear

  • Sees things that others dont see

  • Cant sleep or eat for 3 days in a row

  • Has new symptoms or if current symptoms get worse

  • Shows side effects of medicines

  • Shows behavior that concerns friends, family, or teachers, and others express concern about this behavior and ask you to seek help

Schizophrenia may increase a childs risk for suicidal thinking. 

Is Schizoaffective Disorder Inevitable

Schizoaffective disorder is less common than schizophrenia, bipolar disorder, and depression. However, statistics showing its frequency may be skewed because of the difficulties in diagnosing the disorder. Still, if your first degree relatives are diagnosed with schizoaffective disorder, your risk factors for getting it yourself are much higher than the average person. First-degree relatives are people in your immediate family, like your parents, siblings, and children. Still, just because your relatives get the disorder doesnt guarantee that you will too.

There is no known way to prevent schizoaffective disorder, but general good mental health practices like mitigating stress, getting enough sleep, and a healthy diet and exercise may lower your chance of experiencing certain mental health problems. Otherwise, its important to monitor your mental health for symptoms to catch problems early before they can negatively impact your life.

Psychosocial Factors During Pregnancy And Delivery

Some studies suggest an association between antenatal stress and schizophrenia. The children of mothers whose husband died while they were pregnant have been found to have a significantly increased rate of schizophrenia compared with children who lost their father in infancy in the first year of life. In The Netherlands, rates of schizophrenia have been found to be very slightly higher in individuals exposed in utero to war and flood disaster than in reference subjects.

In the Northern Finland 1966 Birth Cohort the risk of later schizophrenia among unwanted children was elevated 2.4-fold compared with wanted or mistimed children, even after adjustment for confounding by sociodemographic, pregnancy and perinatal variables. Unwantedness might be a marker for features associated with risk in either the mother or the child. In the same cohort, the level of schizophrenia in the offspring of antenatally depressed mothers was elevated by a factor of 1.5-foldly, but the association was not statistically significant. Those mothers of schizophrenia patients with a psychotic first-degree relative had suffered from depressed mood during pregnancy twice as often as other mothers. The familial risk for psychosis, including genetic risk for psychosis, might explain the elevated prevalence of depressed mood during pregnancy among the mothers of the offspring who went on to develop schizophrenia.

Pedigree Studies: Lod Score Methods

In pedigrees with multiple ill individuals, the LOD score method can be used to determine whether the distribution of DNA markers alleles within each pedigree predicts presence of disease. The LOD score is based on a mathematical model of the mode of inheritance . Our uncertainty of the precise mode of inheritance in complex genetic disorder such as schizophrenia introduce the possibility of mis-specifying the model, resulting in inappropriate linkage data.

Brain And Body Risk Factors

Developmental theories of schizophrenia suggest that something goes wrong when the brain is developing. Brain development, from the earliest stage of fetal development, the early years of life and through adolescence, is an extremely complicated process. Millions of neurons are formed, migrate to different regions of the forming brain, and specialize to perform different functions.

The something that goes wrong might be a viral infection, a hormonal imbalance, an error in genetic encoding, a nutritional stress, or something else. The common element in all developmental theories is that the causal event occurs during the brains development.

Even though these potential causes may be rooted in very early development, symptoms of schizophrenia typically emerge in late adolescence or early adulthood.

Linkage Disequilibrium Mapping And Positional Cloning

Positional cloning is the primary strategy available for finding susceptibility genes for disorders with unknown pathophysiology. There are four stages involved in the whole process: genome scan, fine-mapping, LD mapping and functional genomics. Firstly multiple affected families are screened with a DNA marker map of all chromosomes and followed by fine-mapping; in these candidate region, additional markers are genotyped 12 cM apart. The third stage is LD mapping to find the association of small sets of adjacent markers with disease, implicating one or two specific genes. Lastly functional genomics or physiological studies on animal model was initiated to establish the role of the gene and protein, effects of mutation on physiology and behaviour, and response to treatment for the disease.

If Your Siblings Have It

  • If your full sibling has schizophrenia: a risk of 9 in 100
  • If your identical twin has schizophrenia: a risk of 40 to 50 in 100
  • If your non-identical twin has schizophrenia: a risk of 17 in 100

These figures arent fixed. They vary across the world, and science peeps have called for more studies looking at schizophrenia risk in people of African and Latinx ancestry.

What else stirs the pot of schizophrenia?

Family History And The Nature Of Its Relationship To Schizophrenia

Family history in general is the number one predictor for schizophrenia, and by a wide margin. Among the general population the likelihood of any particular individual being diagnosed with schizophrenia is right around one percent, but that number rises by several percentage points when family members have also been diagnosed with the condition.

When one identical twin has been diagnosed with schizophrenia, the chances of the other twin also being diagnosed are 48 percent. This is the highest correlation based on specific family relationship; here are the others:

  • First cousin, uncle, or aunt diagnosed: 2 percent
  • Nephew or niece diagnosed: 4 percent
  • Grandchild diagnosed: 5 percent
  • Half-brother or sister diagnosed: 6 percent
  • One parent diagnosed: 6 percent
  • Full sibling diagnosed: 9 percent
  • One or more children diagnosed: 13 percent
  • Fraternal twin diagnosed: 17 percent

What this list means is that for every schizophrenia sufferer in the general population, there will be six schizophrenia victims among those whose parents have the disorder, nine among those who have schizophrenic siblings, and so on.

Schizophrenia genetic risk factors are real, but they dont completely define or control the disorder. Environmental risk factors and the biological effects they cause are an important supplementary aspect in the causal chain that leads to schizophrenia.

Begin Your Recovery Journey Today.

Looking After Your Physical Health

Schizophrenia takes a toll on your physical health as well as your mental health. It can sap your energy, confidence and motivation you might feel less capable of keeping up your physical health or lose the desire to try.

Another major influence on your physical health is the side-effects of antipsychotic medication. Newer antipsychotic medications have fewer side-effects, but weight gain is still a common one. 

People being treated for schizophrenia are much more likely than the general population to be overweight, have high blood pressure and develop diabetes.

Theyre also more likely to smoke, drink too much and use recreational drugs, which can have a negative effect on your mental and physical health.

If youre struggling with these problems, you may hear your doctor use the term metabolic syndrome. It means you have some combination of:

  • weight gain around the abdomen
  • high blood pressure
  • low levels of the good cholesterol
  • high blood glucose levels.

Metabolic syndrome is common in people with a sedentary lifestyle and unhealthy diet, but its especially common in people with schizophrenia.

There is support to help you get healthy and stay healthy.

Most People With A Sibling Or Parent With Schizophrenia Will Not Develop It

Schizophrenia is a severe disorder that affects about 1 percent of the population.

Is schizophrenia hereditary? Although it clearly runs in families, most people with a relative or even a or parent with schizophrenia will not develop the disorder. The other piece of good news is that the estimates of how heritable it is are declining.

Over the years, researchers have found that the chance of one twin suffering from schizophrenia if the other did was anywhere from 44 to 87 percent. The most common figure cited was 81 percent.

And a 2012 analysis of records for all people in Denmark found that the chance of suffering from schizophrenia if a parent did was 67 percent.

However, the risk may be lower. A 2014 from the Consortium on the of Schizophrenia Family Study in the United States with nearly 300 families concluded that the risk of schizophrenia was only 31 percent within a nuclear family. The groups strategy is to identify endophenotypesspecific symptoms linked to genes. In 2014 the group announced that it had found 12 of these markers. In 2016, it on another 13.

Linking symptoms to genes is essential because the symptoms can be very different from one patient to another, with different genes, as well as other factors, at play.

Most likely, several small variations in genes combine to increase the risk of symptoms. Scientists know that experiences like infections in the womb or during affect the outcome.

A version of this story appears on Your Care Everywhere.

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