An Investigation of SDF1/CXCR4 Gene Polymorphisms in Autism Spectrum Disorder: A Family-Based Study

Autism spectrum disorders (ASD) have a complex pathophysiology including genetic, inflammatory and neurodevelopmental components. We aim to investigate the relationship between ASD and gene polymorphisms of stromal cell-derived factor-1 (SDF-1) and its receptor CXC chemokine receptor-4 (CXCR4), which may affect inflammatory and neurodevelopmental processes.

101 children diagnosed with ASD aged 2-18 and their biological parents were included in the study. All participants were assessed using an information form and the Children were assessed using Childhood Autism Rating Scale (CARS). SDF-1 G801→A and CXCR4 C13→T polymorphisms were detected by genetic techniques. The results were evaluated using the transmission disequilibrium test (TDT) and haplotype relative risk (HRR).

Following TDT evaluation for CXCR4, the assumption of equality was not rejected (χ²=1.385, p=0.239). HRR for the C allele was 1.037 [HRR (95%CI)=0.937 (0.450-2.387), χ²=0.007, p=0.933] and HRR for the T allele was 0.965 [HRR (95%CI)=0.965 (0.419- 2.221), χ²=1.219, p=0.270], but the findings were statistically insignificant. Based on TDT evaluation for SDF1, the assumption of equality cannot be rejected (χ²=0, p=0.999). HRR for the A allele was 0.701 [HRR (95%CI)=0.701 (0.372-1.319), χ²=1.219, p=0.270] and HRR for the G allele was 1.427 [HRR (95%CI)=1.427 (0.758-2.686), χ²=1.219, p=0.270], but the findings were statistically insignificant.

The genetic screening of blood samples from mother, father and child trios could not show a significant association between SDF1/CXCR4 genes and ASD on the basis of TDT and HRR tests. More extensive genetic studies are now needed to investigate the relationship between SDF1/CXCR4 gene polymorphisms and ASD.