BMC MED: Subversion – What is the investigation of the causal relationship between ALS and autoimmune diseases?!

Epidemiological studies have reported associations
between amyotrophic lateral sclerosis (ALS) and different autoimmune diseases.
THIS STUDY, WHICH AIMS TO EXPLORE THE CAUSAL RELATIONSHIP BETWEEN AUTOIMMUNE DISEASES AND ALS USING MENDELIAN RANDOMIZATION (MR), WAS PUBLISHED IN
THE JOURNAL BMC MEDICINE.

To test the genetic predictive effect of responsibility for immune-related outcomes on ALS risk, academics from McGill University in Canada used Europe's largest genome-wide association study (GWAS) summary statistics
for these diseases in a two-sample MR setting.
Single nucleotide polymorphisms (SNPs) closely related to 12 features were extracted from GWAS and their effects
were investigated in a large European ALS GWAS (27,265 versus 110881 controls).
In order to avoid bias in MR tools related to the complex linkage imbalance structure of human leukocyte antigen (HLA) regions, SNPs
within this region were excluded from the analysis.

The results showed that after applying the Bonferroni correction multiplex test, MR analysis showed that responsibility for autoimmune diseases did not affect the risk of
ALS.
Reverse MR analysis also does not support the effect
of ALS responsibility on other autoimmune diseases.
The results of the primary IVW MR analysis were generally supported
by sensitivity MR analysis.
Several sets of SNPs used as MR tools interpreted by the variance of exposure ranged from 8.
1×10-4 to 0.
31
.
Overall, this MR study has a good ability to detect effects of ALS probability (OR) as small as 1.
045 in the main MR and as small as 1.
32 OR
in the reverse MR.

In summary, the MR study does not support a relationship between
responsibility for autoimmune diseases and ALS risk in the European population.
The associations observed in epidemiological studies may be due in part to common biological or environmental confounders
.

References:

Investigation of the causal relationship between ALS and autoimmune disorders: a Mendelian randomization study.
BMC Med 20, 382 (2022).
https://doi.
org/10.
1186/s12916-022-02578-9