Global Haplotype Landscape of SARS-CoV-2 Spike Contact Residues Reveals Dominant Escape Signatures and Systemic Sequencing Ambiguity

Audit of 4.5M SARS-CoV-2 contact residue haplotypes (20 positions, 60 nt each) extracted from global genomes. All sequences length-validated (60 nt). Top haplotype (1M+ copies) encodes Omicron signature (N417, G446, Y449...). 5.64% N-content highlights technical dropout at hypervariable sites. 11k duplicated haplotypes enable lineage tracking. Includes full report, translated top variants, reproducible scripts. Privately uploaded for job applications - available upon request. Derived from real public data.