Advanced Grandparental Age as a Risk Factor for Autism

• ClinicalTrials.gov Identifier: NCT00464477
• Recruitment Status: Completed
• First Posted: April 23, 2007
• Last Update Posted: November 7, 2007
• Sponsor: University of Mississippi Medical Center
• Information provided by: University of Mississippi Medical Center

Tracking Information

• First Submitted Date: April 20, 2007
• First Posted Date: April 23, 2007
• Last Update Posted Date: November 7, 2007
• Study Start Date: June 2007
• Primary Completion Date: Not Provided
• Current Primary Outcome Measures: Not Provided
• Original Primary Outcome Measures: Not Provided
• Current Secondary Outcome Measures: Not Provided
• Original Secondary Outcome Measures: Not Provided
• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: Advanced Grandparental Age as a Risk Factor for Autism
• Official Title: Advanced Grandparental Age as a Risk Factor for Autism and Other Pervasive Developmental Disorders

Brief Summary

The Division of Medical Genetics at the University of Mississippi Medical Center is recruiting parents of children with a pervasive developmental disorder (including autism, autistic spectrum disorder, PDD-NOS, Asperger syndrome, childhood disintegrative disorder, and Rett syndrome) to participate in a study to help determine potential causes of the increasing prevalence of these disorders. The study is being conducted using an anonymous on-line survey available to parents through a secure link.

The study consists of approximately 90 questions about the affected child, siblings, parents, and grandparents, which will take roughly 10-15 minutes to complete. Several families will also be invited to participate in a phone interview. Both the survey and the phone interview are conducted using a self-designated code to protect anonymity and patient privacy. No identifying information such as name, date of birth, address, or phone number will be asked. Only questions regarding the year of birth of family members will be asked.

• Detailed Description: Autism is a genetically heterogeneous entity. Although numerous studies have demonstrated a strong genetic basis, no clear etiology has been identified to date. Recently, two studies have demonstrated an increased risk of autism in children born to fathers over the age of 40. However, given the large male-to-female predominance of autism, it is likely that new mutations on the X chromosome account for a significant number of affected cases. Due to the maternal origin of the X chromosome in males, we hypothesize that advanced maternal-grandpaternal age may also be a risk factor for autism. Precedence for this theory exists with other X-linked disorders such as Duchenne muscular dystrophy and Rett syndrome. Additionally, it has been demonstrated that maternal psychiatric illness, but not paternal psychiatric illness, is more prevalent among parents of children with autism. Using anonymous surveys of families with autistic children, we seek to identify the ages of grandparents at the time the parents were born in order to determine if advanced maternal-grandpaternal age is associated with an increased risk for autism when adjusted for advanced maternal and paternal age. Additionally, we will seek out sister-pairs in order to identify any statistical significance between the ages of the maternal grandfather at delivery of each sister. If advanced maternal-grandpaternal age is, in fact, a risk factor, it would help direct molecular researchers towards genes on the X chromosome as potential etiologies for autism. Also, further study of potential mutagenic exposures in the environment of grandparents may help elucidate the reason for the increasing incidence of autism in recent decades.
• Study Type: Observational
• Study Design: Observational Model: Case-Only; Time Perspective: Retrospective
• Target Follow-Up Duration: Not Provided
• Biospecimen: Not Provided
• Sampling Method: Non-Probability Sample
• Study Population: Patients with any pervasive developmental disorder.

Condition

• Autistic Disorder
• Pervasive Developmental Disorder
• Asperger Syndrome
• Childhood Disintegrative Disorder
• Rett Syndrome

• Intervention: Not Provided
• Study Groups/Cohorts: Not Provided
• Publications *: Not Provided

Recruitment Information

• Recruitment Status: Completed
• Actual Enrollment (submitted: June 18, 2007): 100
• Original Enrollment: Not Provided
• Actual Study Completion Date: October 2007
• Primary Completion Date: Not Provided

Eligibility Criteria

Inclusion Criteria:

• Individuals of any age with autism, autistic disorder, autistic spectrum disorder, Asperger syndrome, pervasive developmental disorder, PDD-NOS, Rett syndrome, or Childhood disintegrative disorder

Sex/Gender

• Sexes Eligible for Study: All

• Ages: Child, Adult, Older Adult
• Accepts Healthy Volunteers: No
• Contacts: Contact information is only displayed when the study is recruiting subjects
• Listed Location Countries: United States

Administrative Information

• NCT Number: NCT00464477
• Other Study ID Numbers: 2007-0023
• Has Data Monitoring Committee: No
• U.S. FDA-regulated Product: Not Provided
• IPD Sharing Statement: Not Provided
• Responsible Party: Not Provided
• Study Sponsor: University of Mississippi Medical Center
• Collaborators: Not Provided

Investigators

• Principal Investigator: Omar Abdul-Rahman, MD; University of Mississippi Medical Center

• PRS Account: University of Mississippi Medical Center
• Verification Date: November 2007