MISSED BY OTHERS, DETECTED BY US
Genomic Unity® Case Study

C9orf72 expansion explains progressive leg weakness

Clinical presentation

A 54-year-old male with a family history of ALS and dementia presented with the following symptoms:

  • Progressive lower leg weakness and spasticity
  • Gait imbalance resulting in falls
  • Ataxia

Previous genetic testing

Testing was performed for multiple maternal relatives with negative results.

Genomic Unity® Testing

was ordered because of its ability to identify all major variant types in a single test.

Results and interpretation

Variantyx Genomic Unity® testing identified a heterozygous, pathogenic GGGGCC repeat expansion in the C9orf72 gene.

The expansion was confirmed internally using Oxford Nanopore long-read sequencing.

Diagnosis: Frontotemporal dementia and/or amyotrophic lateral sclerosis

Combined views of C9orf72 variants

A. Uniform data from short-read WGS identifies one normal allele (5 repeats) and one expanded allele. B. Long-read WGS sizes the expanded allele as ~1,600 repeats.

The Variantyx Difference

Why was this variant detected by Genomic Unity® testing, and not detected by other tests?

  • With such general phenotypes, selecting the right targeted test for a patient is impossible and will lead to a long diagnostic odyssey.
    Variantyx genome analysis detects all major variant types in a single test including small sequence changes, structural variants, mitochondrial variants, and repeat expansions. This is critical for testing of patients with suspected adult onset neurological disorders.

  • When repeat expansions are included in traditional testing, it’s either one gene test or screening testing.
    Only Variantyx genome analysis delivers both repeat expansion sensitivity and specificity, using a combination of short and long-read sequencing, when needed, to provide detection and sizing within a single test.

Want similar results for your patients?

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