Newly Identified RANBP1 Gene may be important in autism disorders, other neuropsychiatric syndromes
Scientists have identified a gene that appears to play a significant role in raising a person’s risk of having more severe subtypes of autism that co-occur with other genetic diseases, such as the chromosomal disorder 22q11.2 deletion syndrome. Variations in this gene, RANBP1, may disrupt brain signaling in different neuropsychiatric conditions—a finding that could open new research opportunities for treatment for multiple neurological diseases.
While abnormal signaling mediated through metabotropic glutamate receptor 5 (mGluR5) is involved in the pathophysiology of Autism Spectrum Disorder (ASD), Fragile X Syndrome and Tuberous Sclerosis, the role of other mGluRs and their associated signaling network genes in syndromic ASD is unknown. This study sought to determine whether mGluR Copy Number Variants (CNV’s) were overrepresented in children with syndromic ASD and if mGluR “second hit” confers additional risk for ASD in 22q11.2 Deletion Syndrome (22q11DS). To determine whether mGluR network CNV’S are enriched in syndromic ASD, we examined microarrays from children with ASD (n = 539). Patient categorization (syndromic vs nonsyndromic) was done via blinded medical chart review in mGluR positive and randomly selected mGluR negative cases. 11.5% of ASD had mGluR CNV’s vs. 3.2% in controls (p < 0.001). Syndromic ASD was more prevalent in children with mGluR CNVs (74% vs 16%, p < 0.001). A comparison cohort with 22q11DS (n = 25 with ASD, n = 50 without ASD), all haploinsufficient for mGluR network gene RANBP1, were evaluated for “second mGluR hits”. 20% with 22q11.2DS + ASD had “second hits” in mGluR network genes vs 2% in 22q11.2DS-ASD (p < 0.014). We propose that altered RANBP1 expression may provide a mechanistic link for several seemingly unrelated genetic and environmental forms of ASD.
Sources and more information
- The Role of mGluR Copy Number Variation in Genetic and Environmental Forms of Syndromic Autism Spectrum Disorder, nature, 19 January 2016.
- Gene may be important in autism disorders, other neuropsychiatric syndromes, medicalxpress, 19 January 2016.
- Newly Identified Gene May Link to Autism and Other Neuro Disorders, genengnews, 20 January 2016.
- RANBP1 gene may increase risk for severe ASD subtypes, healio, January 22, 2016.