• I have a family member with autistic disorder, am I at risk for having a child with autistic disorder?
  Answer ...

• Could autistic disorder still be genetic in my family even if doesn't appear in any other family members?
  Answer ...

• If autistic disorder is inherited, what gene is responsible?
  Answer ...

• How soon will autistic disorder-related genes be found?
  Answer ...

How many genes are involved in causing autistic disorder? Answer ... Some reports say that autistic disorder is caused by inheriting specifically the mother's genes or the father's genes. Is this true? Answer ...

• What is the difference between PDD/NOS, Asperger disorder, and Autistic disorder?
  Answer ...

• Are there different genes involved in each pervasive developmental disorder?
  Answer ...

• Why do more males have autistic disorder than females?
  Answer ...

• How do researchers look for the genes that contribute to autistic disorder?
  Answer ...

• Can I find out if my child's autistic disorder is inherited by participating in a research study?
  Answer ...

• Why are so many genetic studies being conducted now?
  Answer ...

Asperger Disorder
Asperger disorder, sometimes referred to as Asperger syndrome, is a neurobiological disorder. In contrast to autistic disorder, individuals with Asperger disorder do not have a delay in spoken language development. However, they can have serious deficits in social and communication skills. They often have obsessive, repetitive routines and preoccupations with a particular subject matter.

Pervasive Developmental Disorder Not Otherwise Specified (PDD/NOS)
PDD/NOS is a diagnosis often considered for children who show some signs of autistic disorder, but who do not meet the specific diagnostic criteria for the other PDDs.

Rett Disorder
Rett disorder is a complex neurological disorder that affects mainly girls, but there are reports of males who this disorder. Rett disorder is genetic in origin, and is among the most common genetic cause of profound intellectual and physical disability in girls, occurring more commonly than 1 in 10,000 female births. Individuals with Rett disorder develop normally until 6 to 18 months of age followed by a developmental regression. This regression is followed by a deceleration of head growth, loss of purposeful hand movements and followed by the appearance of midline, stereotypic hand movements. A gene for Rett disorder was identified in 1999.

Childhood Disintegrative Disorder
Children with childhood Disintegrative disorder develop normally for a relatively prolonged period (usually 2 to 4 years) before developing a condition that resembles autistic disorder. Typically language, interest in the social environment, and often toileting and self-care abilities are lost, and there may be a general loss of interest in the environment.