Attention-deficit hyperactivity disorder (ADHD) is a common childhood disorder which occurs more often in twins than singletons.
Unfortunately, they also share the risk of having ADHD. According to an Australian study , twins are more likely to have ADHD than singletons. Additionally, a child who has an identical twin with ADHD has a high chance of also developing the disorder.
If something like ADHD were genetic, then identical twins with ADHD would be more alike than fraternal twins. What twin studies have found is that seventy percent of the variation in ADHD traits is influenced by genes, and the remaining thirty percent is due to environmental factors.
Anita Thayer, M.D. analyzed the DNA from 366 children with ADHD. A comparison with DNA from unaffected patients showed an abnormality in the sequences. Thayer's study shows that the ADHD group of children had larger and more frequent variations. Fathers with ADHD will pass this code discrepancy to offspring.
Boys (13%) are more likely to be diagnosed with ADHD than girls (6%). Black, non-Hispanic children and White, non-Hispanic children are more often diagnosed with ADHD (12% and 10%, respectively), than Hispanic children (8%) or Asian, non-Hispanic children (3%).
Greatest heredity from mother
- 40 percent of these boys are themselves diagnosed with the condition, says Solberg. The greatest inheritance was from the mother to the children.
ADHD tends to run in families and, in most cases, it's thought the genes you inherit from your parents are a significant factor in developing the condition. Research shows that parents and siblings of someone with ADHD are more likely to have ADHD themselves.
While the exact causes of ADHD have not been identified, genetic studies show there is a strong hereditary component, with an up to a 91 percent likelihood of passing the disorder to your children.
ADHD is a common neurodevelopmental disorder with onset of symptoms typically in early childhood. First signs of the disorder, including language delay, motor delay and temperament characteristics, may be evident as early as infancy.
Parents' reported proportions of probable behavioural/emotional disorders did not differ between the twin and singleton girls, but among the twin boys there was a nonsignificant trend of being more often probably disturbed. Twins were reported to be less disturbed than singletons according to the teachers' assessments.
The risk of attention deficit hyperactivity disorder (ADHD) increases for firstborn children compared with the youngest born and single children, according to a German study published in the Journal of Attention Disorders.
The risk of depression, psychosis, or suicide in first-degree relatives of index cases of bipolar disorder is 20–25 percent. The same risk is found in fraternal twins, but it is about 70 percent in identical twins, leading to a monozygotic–dizygotic risk ratio of more than 3:1.
Heritability in ADHD
According to a recent meta-analysis of twin studies, the heritability of ADHD is estimated at 77–88% [8]. The magnitude is therefore similar to that of autism spectrum disorder (about 80%), bipolar disorder (about 75%), and schizophrenia (about 80%) [6].
That's because twins are born prematurely 60 percent of the time and land in the costly neonatal intensive care unit more often than singletons. The article also mentions that these babies are more susceptible to mental retardation and learning disabilities.
Whether it be due to shorter gestation, premature birth, or maternal health issues, twins are at a higher risk of being born with Special Needs (SPNs).
ADHD, also called attention-deficit disorder, is a behavior disorder, usually first diagnosed in childhood, that is characterized by inattention, impulsivity, and, in some cases, hyperactivity.
Many children (perhaps as many as half) will outgrow their symptoms but others do not, so ADHD can affect a person into adulthood.
Barkley, PhD. “Children diagnosed with ADHD are not likely to grow out of it. And while some children may recover fully from their disorder by age 21 or 27, the full disorder or at least significant symptoms and impairment persist in 50-86 percent of cases diagnosed in childhood.
So, are you born with ADHD? Yes, the disorder tends to run in families – but you may not display the symptoms throughout your whole life. Being born with ADHD is known to have its limiting factors, but with support in managing your symptoms, you can expect to see great improvements.
Overall population incidence is felt to be 8%-10%. Several investigations have demonstrated that children who have ADHD usually have a least one close relative (child or adult) who also has ADHD. At least one-third of all fathers who have ADHD will produce a child with ADHD.
Attention deficit hyperactivity disorder (ADHD), one of the most prevalent childhood disorders today, is generally more likely to be diagnosed and treated in boys than in girls.
You can increase the chance of your child not having ADHD by staying healthy throughout your pregnancy. A healthy diet and regular doctor visits are important. So is avoiding the use of alcohol and drugs. Children whose mothers smoked while they were pregnant are twice as likely to develop ADHD.
ADHD runs in families. Anywhere from one-third to one-half of parents with ADHD will have a child with the disorder. There are genetic characteristics that seem to be passed down. If a parent has ADHD, a child has more than a 50% chance of having it.
Both genetic and environmental factors are associated with numerous mental health disorders. Researchers have found that birth trauma might be linked to children developing attention-deficit hyperactivity disorder (ADHD) in childhood.