Table 3.

Candidate genes in each of the primary biological pathways.

Gene Symbol	Sleep Phenotype	Syndrome Associated with Autism
Dopaminergic Synapse
MAOA	Poorer sleep quality; lower sleep efficiency (indexed by higher quantitative sleep disturbance scores); insomnia	Brunner Syndrome
SCN1A	Increased sleep disturbances; abnormal non-rapid eye movement sleep architecture; sleep dysregulation	Early Infantile Epileptic Encephalopathy; Dravet Syndrome
CACNA1C	Increased (longer) sleep latency; reduced REM Sleep	Timothy Syndrome
SLC6A3	Sleep-wake cycle; sleep architecture	N/A
Serotonergic Synapse
MAOA	Sleep-wake cycle—including lower homeostatic drive; poorer sleep continuity.	N/A
CACNA1C	Shorter sleep duration; fatigue; early morning awakening	Wu Type of X-linked Syndromic Mental Retardation
HTR2A	Obstructive sleep apnea, chronic fatigue syndrome	N/A
SLC6A4	Increased risk of sleep bruxism; increased complaint of sleep onset problems; shorter sleep duration	N/A
MECP2 and Associated Rett Syndrome
MECP2	Phase-specific sleep loss; sleep fragmentation; increased daytime napping with age;	Rett Syndrome
BDNF	Regulation of sleep slow wave oscillations; decreased spectral power in the alpha band in stage one and decreased theta power in stages two and three of nonrapid-eye-movement sleep	N/A
RBFOX1	Sleep timing	N/A
UBE3A	Short sleep duration; increased sleep onset latency; reduced capacity to accumulate sleep pressure	Angelman Syndrome
SIDS Susceptibility Pathways
MECP2	Phase-specific sleep loss; sleep fragmentation; increased daytime napping with age;	Rett Syndrome
BDNF	Regulation of sleep slow wave oscillations; decreased spectral power in the alpha band in stage one and decreased theta power in stages two and three of nonrapid-eye-movement sleep	N/A
SLC6A4	Increased risk of sleep bruxism; increased complaint of sleep onset problems; shorter sleep duration	N/A
MAOA	Poorer sleep quality; lower sleep efficiency (indexed by higher quantitative sleep disturbance scores); insomnia	Brunner Syndrome