FASD: Heart defects caused by altered function, not structure?

Recent data shows that more than 500,000 women in the U.S. report drinking during pregnancy, with about 20 percent of this population admitting to binge drinking.

Even one episode of heavy drinking can lead to the collection of birth defects known as fetal alcohol syndrome (FAS).

Along with growth retardation, head and face abnormalities, and neurological problems, FAS also causes heart problems in just over half of those with this condition.

Though much research has focused on looking for the cause of these alcohol-induced heart defects, they remain largely a mystery.

To investigate this question, Ganga Karunamuni of Case Western University and her colleagues studied heart formation in quail embryos, whose heart development is very similar to that of humans.

The researchers used an innovative imaging technique, optical coherence tomography, to compare embryos exposed to a single, large dose of alcohol to those who hadn't received alcohol.

They looked both at how alcohol changed the function of the developing hearts as well as their structure.

They found that significant changes in heart function appeared to come well before changes in structure that are hallmarks of the well-known FAS heart anomalies.

These changes in function, the study authors suggest, might be the cause of the structural problems that arise later by exerting forces on the heart that change its development.

The article is entitled "Ethanol Exposure Alters Early Cardiac Function in the Looping Heart: A Mechanism for Congenital Heart Defects?"

It appears in the Articles in Press section of the American Journal of Physiology – Heart and Circulatory Physiology, published by the American Physiological Society.

Results
As expected, the researchers found that the hearts of embryos exposed to alcohol had dramatic defects close to hatching, including thinner walls separating the heart's four chambers and damaged valves.

Long before these defects formed, the researchers saw significant differences in heart blood flow between embryos that weren't exposed to alcohol and those that were.

In those whose shells weren't injected with alcohol, a small portion of the blood flowed backward through the heart circuit after each beat.

In those exposed to alcohol, a much larger portion of blood flowed backward in the circuit.

These malfunctioning hearts had smaller "cardiac cushions"—collections of cells that later become chamber walls and valves—compared to unexposed hearts.

More information: ajpheart.physiology.org

Good Parenting: There is no definitive Rule Book

Any parent will tell you that there is no simple recipe for raising a child. Being a parent means getting hefty doses of advice – often unsolicited – from others.

But such advice often fails to consider a critical factor: the child. A new review of dozens of studies involving more than 14,600 pairs of twins shows that children's genetics significantly affect how they are parented.

Reut Avinun

"There is a lot of pressure on parents these days to produce children that excel in everything, socially and academically," says Reut Avinun of the Hebrew University of Jerusalem.

"Since children are not born tabula rasa, I felt it was important to explore their side of the story, to show how they can affect their environment, and specifically parental behaviour."

Most studies of parenting look at only the reverse, how parents affect their children's experiences.

To explore the flip side, Avinun and Ariel Knafo looked to twins. They reasoned that if parents treat identical twins, who share 100 percent of their genes, more similarly than non-identical twins, who share on average 50 percent of their genes, then it suggests that the child's genes shape parenting.

Indeed, across 32 studies of twins, they found that children's genetically-influenced characteristics do affect parental behavior.

As published in Personality and Social Psychology Review, they estimated that 23 percent of differences in parenting is due to a child's genetics.

The genotype-related differences are ways that the children evoke different responses from their environment.

For example, a child that is antisocial is more likely to elicit harsh discipline from parents than a more social child.

In one recent study, Knafo's research group found that boys with less self-control are more likely to experience lower levels of positive maternal behaviour.

For boys, but not for girls, a particular genotype – a polymorphic region in the gene that codes for the serotonin transporter – predicted mothers' levels of positive parenting and the boys' level of self-control.

"In other words, boys' genetically influenced level of self-control affected the behaviour of their mothers toward them," Avinun says.

Avinun and Knafo also found that children's shared environment – socioeconomics, cultural exposure, etc. – accounts for 43 percent of parenting differences.

And the non-shared environment – different schools, friends, etc. – accounts for 34 percent of the differences.

Importantly, the study's findings support the idea that parenting does not necessarily affect children in the same family, in a similar way.

Several factors affect the extent to which genetics influence parenting. Avinun and Knafo found, for example, that age was important, supporting the argument that the child's genetic influence on parenting increases with age.

"As children become increasingly autonomous, their genetic tendencies are more likely to be able to affect their behaviour, which in turn influences parental behaviour," Avinun says.

The research in total, Avinun says, "means that parenting should not be viewed solely as a characteristic of the parent, but as something that results from both parental and child attributes."

Therefore, any interventions or treatments to help parenting should consider both the parents and children, and could vary even within a family.

"The discussion of 'nature vs. nurture' has transformed into 'nature and nurture.' We now understand that most characteristics are determined by the interplay between genetic and environmental influences," Avinun says.

Because children are born differently, there never can be a general rule book for raising children, she explains.

"There isn't one style of ideal parenting. Each child requires a different environment to excel. So parents should not invest a lot of effort in trying to treat their children similarly, but instead, be aware of the variation in their children's attributes and nurture them accordingly."

More information:
The study, "Parenting as a Reaction Evoked by Children's Genotype: A Meta-Analysis of Children-as-Twins Studies" by Reut Avinun and Ariel Knafo, was published online on August 12, 2013, and is forthcoming in print in November 2013 in Personality and Social Psychology Review: psr.sagepub.com/content/early/2013/08/12/1088868313498308

Dyslexia: It's NOT a Vision Problem! It's a Cognitive Disorder!

A collaborative paper published in the journal Pediatrics, has been written by the American Academy of Pediatrics, Section on Ophthalmology, Council on Children with Disabilities, American Academy of Ophthalmology, American Association for Pediatric Ophthalmology and Strabismus, American Association of Certified Orthoptists, which concluded that Dyslexia is NOT a vision problem and cannot be 'cured' by eye exercises, behavioural vision therapy, or special tinted filters or lenses.

Abstract
Learning disabilities, including reading disabilities, are commonly diagnosed in children. Their etiologies are multifactorial, reflecting genetic influences and dysfunction of brain systems.

Learning disabilities are complex problems that require complex solutions. Early recognition and referral to qualified educational professionals for evidence-based evaluations and treatments seem necessary to achieve the best possible outcome.

Most experts believe that dyslexia is a cognitive /language-based disorder. Vision problems can interfere with the process of learning; however, vision problems are not the cause of primary dyslexia or learning disabilities.

Scientific evidence does not support the efficacy of eye exercises, behavioural vision therapy, or special tinted filters or lenses for improving the long-term educational performance in these complex pediatric neurocognitive conditions.

Diagnostic and treatment approaches that lack scientific evidence of efficacy, including eye exercises, behavioral vision therapy, or special tinted filters or lenses, are not endorsed and should not be recommended.

Summary
Dyslexia and learning disabilities are complex problems that have no simple solutions. The most widely accepted view is that dyslexia is a language-based disorder.

The American Academy of Pediatrics, the American Academy of Ophthalmology, the American Association for Pediatric Ophthalmology and Strabismus, and the American Association of Certified Orthoptists strongly support the need for early diagnosis and educational intervention.

Recommendations for multidisciplinary evaluation and management must be based on evidence of proven effectiveness that is demonstrated by objective scientific methodology. It is important that any therapy for learning disabilities be scientifically established to be valid before it can be recommended for treatment.

Currently, there is no adequate scientific evidence to support the view that subtle eye or visual problems cause learning disabilities.

Furthermore, the evidence does not support the concept that vision therapy or tinted lenses or filters are effective, directly or indirectly, in the treatment of learning disabilities.

Thus, the claim that vision therapy improves visual efficiency cannot be substantiated. Diagnostic and treatment approaches that lack scientific evidence of efficacy are not endorsed or recommended.

With early recognition and individualized, interdisciplinary management strategies, children with learning disabilities can enjoy successful academic experiences.

Read the full text of the paper at THE AMERICAN ACADEMY OF PEDIATRICS