_1757587592 20250911104632000 Rovedar Daryoushbabazadeh@gmail.com Rovedar Journal of World’s Poultry Science J. World's Poult. Sci. 2980-7999 09 01 2025 4 3 Abdul Rehman https://orcid.org/0009-0009-3221-2984 Nauman Khan https://orcid.org/0009-0008-1289-6859 M Khuzema Niaz https://orcid.org/0009-0009-2039-3570 Ali Mujtaba Shah https://orcid.org/0000-0003-3698-6775 Javed Zafar https://orcid.org/0009-0005-3299-1800 Fasih Ur Rehman https://orcid.org/0000-0002-7750-3453 Naseer Ahmad https://orcid.org/0009-0005-8967-6203 Kassahun Bekana https://orcid.org/0000-0001-9393-2912 Muhammad Mushahid https://orcid.org/0000-0001-8670-3011 Muhammad Talal https://orcid.org/0009-0009-7272-9355 Umar Aziz https://orcid.org/0009-0009-6266-4340 Introduction: The Australorp chicken, known for its exceptional egg production and adaptability, is a valuable genetic resource for the poultry industry. However, the molecular basis underlying their distinctive traits remains poorly understood. The present study aimed to identify novel genes and genetic variants associated with key production traits in Australorp chickens by performing a comprehensive comparative genomic analysis combined with an in silico genome-wide association study (GWAS).Materials and methods: Whole-genome sequencing data from 12 Australorp chickens were compared with data from four other breeds, including ten Rhode Island Red, eight Leghorn, ten Plymouth Rock, and six Red Jungle Fowl. Quality control and preprocessing were applied to ensure high-quality genomic data for downstream analyses. Comparative genomic analysis revealed several breed-specific genetic variants in Australorp chickens, affecting 50 genes functionally involved in metabolic and reproductive pathways, and 30 genes with reduced or altered functional annotations compared to other breeds. Principal component analysis revealed clear genetic differentiation among Australorp chickens, confirming their distinct genetic structure.Results: In silico GWAS identified significant associations between novel candidate genes (GENE 42, GENE 89) and key production traits, including egg production, egg weight, and disease resistance. Functional annotation revealed that these genes, identified in Australorp chickens (Gallus gallus), are mainly involved in metabolic processes, immune response, and reproductive pathways. 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