Better understanding of autism genes

A number of genes are believed to be involved in autism, but so far only mixed results in effort to identify them.

By JUDY SIEGEL-ITZKOVICH
Brain 311 T (photo credit: Thinkstock/Imagebank)
Brain 311 T
(photo credit: Thinkstock/Imagebank)
A number of genes are believed to be involved in autism, but so far there have been only mixed results in the effort to identify them.
The reason for this is that autism is influenced by many different genes, and different genes are involved in different individuals, making it hard to find the common genetic ground between patients.
Now, research conducted at the Hebrew University has shown that despite this, the various genes that play a part in autism all tend to be involved in specific processes in the brain.
The research, conducted by Dr. Sagiv Shifman and his doctoral student Eyal Ben-David at HU’s genetics department, has potential implications for early diagnosis and for future treatment of autism, and was published in the journal PLoS Genetics.
Autism spectrum disorders are neurodevelopmental syndromes characterized by social deficits, language impairments and repetitive behaviors. Recent studies indicate that autism is considerably more common than previously supposed, with a prevalence rate as high as one percent in some regions.
Boys are more likely to have it than girls.
The main goal of the project was to test the contribution of rare genetic mutations, as well as the genetic variations common in the population and to see whether these genetic risk factors are related.
Instead of testing individual genes, the researchers chose to study gene collections, in an attempt to understand the general pathways involved in autism.
To that end, the scientists constructed a network based on the expression pattern of genes across different brain areas. This allowed them to discover groups of genes with shared function in the brain.
Next, based on genetic data from thousands of families with autistic children, the researchers studied the contribution of different groups of genes to autism.
To their surprise, they found – when looking at mutations found in autism as well as thousands of common gene variants that are more frequently seen in autistics – that these mutations and variations are located in specific functional groups.
When looking at families with only one autistic individual (sporadic cases) and in families where there is more than one affected individual (multiplex cases), the same variants were seen acting in both cases. These groups of genes are highly active in the first year of life, and are involved in processes of learning, memory and sensory perception.
The researchers believe their work could pave the way for large-scale genetic scans in the future that could lead to early diagnosis of autism. The results of their study may also provide a ray of hope that by concentrating on specific gene groups, it will one day be possible to design drugs for alleviating symptoms in autistic people with different genetic backgrounds.
Sleep apnea, in which people stop breathing momentarily many times a night because of obstructions in their respiratory system, is a serious business. It can be relieved by continuous positive airway pressure (CPAP) devices, which are quite expensive but very effective. Research at Ben-Gurion University of the Negev and Soroka University Medical Center in Beersheba has found that cost deters many people from getting help, as the devices are not paid for by the health funds. The study by Profs. Ariel Tarasiuk and Haim Reuveni and colleagues was recently published in the journal PloS One.
As a matter of health policy, they recommend financial incentives to encourage CPAP treatment, especially among vulnerable populations. Such a policy would prioritize out-of-pocket expenditures based on service value and not its cost.
“Implementation of a value-based insurance strategy for CPAP treatment would prioritize high-value care based on its potential clinical and economic benefit,” the two argue.
The disorder, which affects two to nine percent of the adult population, can lead to significant cardiovascular morbidity and mortality. If used on a regular basis, CPAP can effectively decrease daytime sleepiness; reduce cardiovascular morbidity, improve quality of life and reduce health care costs.
Yet many patients, mainly of lower socioeconomic status, do not purchase the CPAP device if the healthcare system requires high cost sharing, they write. Cost sharing is an accepted expenditure-control strategy. It reduces consumer demand for health care services in every health care system studied.
Here, according to the National Health Insurance Law, CPAP treatment requires a mandatory out-of-pocket copayment, ranging from 25% to 50% ($330 to $660) of the cost of a CPAP device (average cost of the device is $1,320), depending on the patient’s supplementary health insurance coverage.
Financial incentive polices in the health care system have been proposed as a strategy to promote high-value health care as in the case of CPAP treatment based on the potential for clinical benefit and to minimize the health risk of not treating with CPAP.