Illumina presented pilot data from a GeneDx collaboration showing its Constellation mapped‑read technology can detect variants that elude traditional short‑read methods, including repeat expansions, complex structural variants and regions with high homology. The pilot used NovaSeq X Plus systems and compared Constellation calls to orthogonal methods such as long‑read sequencing and arrays. GeneDx reported improved detection in clinically relevant loci like DMPK, SMN1 and NCF1, suggesting mapped reads can bridge the gap between short‑read throughput and long‑range information. Illumina framed Constellation as enabling long‑range insight without sacrificing the cost and scale advantages of established short‑read platforms. Clinical labs and rare‑disease programs will test the technology’s sensitivity, specificity and integration cost. Success in broader validation could shift diagnostic workflows and reduce the need for reflex long‑read testing for hard‑to‑map regions.