Surprising Biological Markers of Autism

biological markers of autism

Autism is a disorder which impacts greatly upon a baby’s ability to mature and acquire normal social skills; the condition causes children to communicate in odd speech patterns such as speaking repetitively or echoing the speech of others. For some time scientists believed that autism could only be detected when a child had grown old enough to be able to speak with others. However recent studies conducted by researchers at the University of Kansas have suggested that autism may soon be detectable even before a child learns the alphabet. The researchers provided evidence that the level of the enzyme salivary alpha-amylase (sAA), within a child diagnosed with autism spectrum disorder (ASD) is usually higher and more stable than infants maturing without this condition. They also claimed that children with autism have larger resting pupil sizes than their normally growing counterparts.

[showmyads]These conclusions were drawn after a series of tests were carried out. Samples of the enzyme were first taken from a group of autistic children and then from another group of regular growing youngsters. The levels of salivary alpha-amylase (sAA) were examined and found to be lower for the autistic children than for the normally developing children during the afternoon period.

Sampling during daylight hours, however, had a different outcome. Tests conducted at the homes of the participants showed that sAA levels were higher and more stable for this daytime period with the autistic children.

Assistant research professor Christa Anderson thus surmised that the autonomic system of children with ASD must consistently remain on the same level throughout the day, which is in stark contrast to the rise and fall of sAA in normally developing children.

The scientists then compared three groups of children between the ages of 20 and 72 months. The first group contained children diagnosed with ASD, the second group contained normally developing infants and the third group contained toddlers with Down syndrome.  “The group of normally developing children, showed a gradual rise in the levels of sAA and a plunge over the course of the day,” said Christa Anderson.

Norepinephrine (NE) is a neurotransmitter which is present in the blood plasma levels of individuals with autism, and is linked to sAA release. However some researchers suggested that the presence of NE was possibly due to the stress caused by the blood being drawn from the participants.

In an effort to rid the study of this problem, the researchers then  collected saliva through a virtually stress free procedure of placing a highly absorbent sponge under the participant’s tongue.

Gathering sAA levels today can aid doctors in diagnosing children with autism spectrum disorder (ASD) much earlier than before a child begins to speak. The process of early diagnosis may then provide parents with the necessary time to facilitate the proper treatment of the disorder.

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