Causal relationships between skin microbiome and pathological scars: a bidirectional mendelian randomization study

Skin bacteria infection could be a potential risk factor on wound scar formation, yet the specifics of this relationship are not fully understood. This research investigates the causal relationships between specific skin microbiome and these diseases by using bidirectional Mendelian randomization (MR). This study employed a bidirectional MR analysis using genome-wide association study (GWAS) data to analyze the associations between skin microbiome and pathological scar. Single nucleotide polymorphisms (SNPs) served as instrumental variables (IVs) in MR methods, including inverse variance weighted (IVW), and MR Egger. The IVW analysis suggested a significant relationship between specific skin microbiome and pathlogical scars. Actinomycetales_Sebaceous, Proteobacteria_Sebaceous, ASV072[Paracoccus (unc.)]_Dry, ASV008[Diaphorobacter nitroreducens]_Dry, Pseudomonadales_moist, ASV001[Propionibacterium acnes]_Moist, Moraxellaceae_moist, Flavobacteriaceae_Dry were significantly associated with keloid. Chryseobacterium_Moist, ASV016[Enhydrobacter(unc.)]_Moist, ASV021[Micrococcus(unc.)]_Moist, ASV022[Streptococcus salivarius]_Moist, Rhodobacteraceae_Dry, Staphylococcus_Moist, Micrococcaceae_Moist, ASV007[Anaerococcus(unc.)]_Dry, Betaproteobacteria_Moist and ASV001[Propionibacterium acnes]_Moist were significantly associated with hypertrophic scarring. Reverse MR analysis indicates both keloid and hypertrophic scar regulated the composition of the skin microbiome. The study revealed a possible correlation between some specific skin microbiome and pathlogical scars. Understanding these inverse relationship could help improve clinical treatment and reducing pathological scar formation.