Should Autistic Children Be Tested for the PTEN Mutation?

Recently, my family visited a genetic counselor at Arkansas Children's Hospital in Little Rock, Arkansas to discuss the positive genetic test results of my six year old son and four year old daughter. Because the PTEN gene is a large gene the range of expression varies widely. One sign present in almost all people positive for this mutation is a head size that is at least in the 97 to 99^th percentile (macrocephaly). This same characteristic is often present in children who have autism. Twenty percent of people with a known PTEN mutation have autism.

While at our consultation, the counselor told me there is a debate about whether children who knowingly have autism should be tested for the mutation because it can and often does cause specific cancers. A study performed by The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital (OSU CCC-James) and Richard J. Solove Research Institute and Children's Mercy Hospitals and Clinics, Kansas City, Mo. tested 18 children between the ages of 3 to 18 years who had an autism spectrum disorder and macrocephaly. The study found three males were positive for the mutated gene (17 percent).

Researchers S. Shiovitz, J. Everett, SC Huang , MS Orloff , C Eng , and SB Gruber conducted a clinical study comparing head circumference to the detection of a PTEN mutation and higher breast cancer risk among women. Results showed of the twenty-eight women tested the positive predictive value was 14 percent for a PTEN mutation. Additional clinical symptoms are needed for the consideration of this specific mutated gene but this study does not undo the previous one. These subjects were women, presumably without autism but with the macrocephaly characteristic.

Though certainly mice are not humans, much scientific testing is done on them. Researchers at Massachusetts Institute of Technology have found the mutated PTEN gene and the mutated serotonin transporter gene are involved in the display of autistic behaviors in mice. A mutation in both genes caused the expression of these behaviors to be more severe. The results of this study therefore indicate that both a mutated PTEN gene and mutated serotonin transporter gene may cause a more severe expression of autism.

Backlash exists on whether or not this testing of children who have autism is a good idea with a lot of the backlash being from parents of autistic children. Because of the high rates of pregnancy terminations of babies with Down syndrome, they fear autistic children will face the same fate if something that indicates the child will have autism is known. A positive test for this mutation during the fetal period by the use of an amniocentesis does not necessarily indicate the child will be autistic or have any major medical problems-only the mutated gene. As I previously stated, those with this mutation present in many different ways. A prenatal test currently exists for this specific mutation but is not normally run due to PTEN conditions being uncommon and the test being expensive. Although many cases remain undefined, at least 1 in 200,000 people have Cowden Syndrome and other PTEN mutation expressions.

While the fear that children with a PTEN mutation and/or additional conditions that may cause autism will be aborted, cancer is also a fear if they are allowed to live. This mutation causes a susceptibility to cancer and those who have it need to be recognized so screening can be available for them. My life has been a product of not being screened for cancer and barely catching the disease on time until my 2007 diagnosis of a duplicate A nucleotide in the PTEN gene.

Inevitably if a conclusive gene for autism is found, abortions for that reason will likely increase because the issues from PTEN are difficult to manage. Mothers and fathers of children who have autism realize how special children with autism are though many of us also realize others are not emotionally equipped to deal with the situation. An autistic child who has already been born and has this mutated gene needs to be identified for cancer screening or an even more grievous wrong has been committed. In the future the child could develop cancer and it may be too late to save his or her life.