The RAY1/ST7 tumor-suppressor locus on chromosome 7q31 represents a complex multi-transcript system.

Area of Science:

• Genetics
• Molecular Biology
• Neuroscience

Background:

• The RAY1 (FAM4A1) gene, located at a translocation breakpoint in autism, has conflicting reports regarding its role as a tumor suppressor (ST7).
• The RAY1/ST7 locus is complex, involving multiple genes and alternative splicing.

Purpose of the Study:

• To comprehensively analyze the RAY1/ST7 locus and its associated genes.
• To investigate sequence variants in RAY1/ST7 and related noncoding genes in autism probands.

Main Methods:

• Detailed analysis of the RAY1/ST7 locus, including gene structure and alternative splicing.
• Screening of RAY1/ST7 and ST7OT1-3 exons for sequence variants in 90 autism probands and a control population.

Main Results:

• The RAY1/ST7 locus comprises a multigene system with sense and antisense noncoding genes (ST7OT1-4) overlapping RAY1/ST7 transcripts.
• At least 18 RAY1/ST7 isoforms are generated, with potential for more through alternative splicing and use of ST7OT3/ST7OT4 exons.
• Several rare sequence variants, including Ile361Val, were found in autism probands but not controls; their pathogenicity is uncertain.
• The noncoding genes at the locus may function as regulatory RNAs.

Conclusions:

• The RAY1/ST7 locus is a complex genetic region with extensive alternative splicing and potential regulatory elements.
• While rare variants were identified in autism patients, their role in the disorder requires further investigation.
• The noncoding transcripts at this locus may play a role in gene regulation, potentially impacting neurological development.