- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: IEA. (OMIM:608631)
- Autism (HP:0000717): Autism is a neurodevelopmental disorder characterized by impaired social interaction and communication, and by restricted and repetitive behavior. Autism begins in childhood. It is marked by the presence of markedly abnormal or impaired development in social interaction and communication and a markedly restricted repertoire of activity and interest. Manifestations of the disorder vary greatly depending on the developmental level and chronological age of the individual (DSM-IV). Evidence: IEA. (OMIM:608631)
- Reduced ability to form peer relationships (HP:0000728): Difficulty to establish relations with others in a comparable social group (peers) that may be manifested in pehnomena such as not being able to initiative a conversation, understand social cues, or to discuss shared interests. This feature is associated with poor integration within a community or group. Evidence: IEA. (OMIM:608631)
- Restrictive behavior (HP:0000723): Behavior characterized by an abnormal limitation to a few interests and activities. Evidence: TAS. (OMIM:608631)
- Motor stereotypy (HP:0000733): Use of the same abnormal action in response to certain triggers or at random. They may be used as a way to regulate one's internal state but must otherwise have no apparent functional purpose. Evidence: TAS. (OMIM:608631)
- Non-Mendelian inheritance (HP:0001426): A mode of inheritance that depends on genetic determinants in more than one gene. Evidence: IEA. (OMIM:608631)
- Abnormal nonverbal communicative behavior (HP:0000758): Abnormalities in eye contact, communicative facial expressions, gesture use, or the use of others' bodies to communicate convey shared meanings within a culture that replace or supplement verbal communication. Evidence: IEA. (OMIM:608631)
- Sporadic (HP:0003745): Cases of the disease in question occur without a previous family history, i.e., as isolated cases without being transmitted from a parent and without other siblings being affected. Evidence: IEA. (OMIM:608631)
- Lack of spontaneous play (HP:0000721). Evidence: IEA. (OMIM:608631)
- Inflexible adherence to routines (HP:0000732): A need to strictly adhere to repetitive routines or patterns of behavior which are created by the environment. One becomes upset or distressed when their routines are disrupted or altered. Evidence: IEA. (OMIM:608631)
These phenotypes are associated with the disease asperger syndrome, susceptibility to, 2 (OMIM:608631).