Genetics of digital osteoarthritis

Area of Science:

• Genetics
• Rheumatology
• Osteoarthritis Research

Background:

• Genetic factors play a substantial role in digital osteoarthritis development, with heritability estimated between 48% and 65%.
• Digital osteoarthritis manifestations exhibit complex inheritance patterns, including Mendelian for Heberden's nodes and multifactorial for other forms, influenced by genes and environment.
• Challenges in molecular studies include defining the phenotype and the late onset of symptoms.

Purpose of the Study:

• To review the current understanding of genetic factors contributing to digital osteoarthritis.
• To highlight key findings from genetic association and genome-wide studies.
• To discuss challenges and future directions in digital osteoarthritis genetics research.

Main Methods:

• Review of genetic association studies, including candidate-gene and genome-wide association studies (GWAS).
• Analysis of Mendelian inheritance patterns for specific digital osteoarthritis manifestations.
• Examination of gene polymorphisms and their association with osteoarthritis.

Main Results:

• Genome-wide scans identified multiple susceptibility loci for digital osteoarthritis, with some replicated at 2p, 2q, 3p, 4q, and 7p.
• Conflicting results were reported for HLA gene associations.
• Polymorphisms in genes such as A2BP1, AGC1, ASPN, ENPP1, HFE, KL, VDR, and IL-1/IL-6 clusters showed associations, though not always reproducible.
• Telomere shortening was observed in women with hand osteoarthritis, suggesting a link to aging processes.

Conclusions:

• Digital osteoarthritis is significantly influenced by genetic factors, necessitating further research into specific genes and pathways.
• Replication of GWAS findings and consistent validation of candidate-gene associations are crucial for advancing the field.
• Understanding the interplay between genetic predisposition and environmental factors is key to unraveling the etiology of digital osteoarthritis.