What the study found
Tandem repeat (TR) mutations were more likely to occur at loci that were longer, had uninterrupted motif sequences, and were heterozygous in the parental germline. The study also found that children born to older fathers had more de novo mutations at short tandem repeats (STRs), and that 43 TR loci were hyper-mutable in the family studied.
Why the authors say this matters
The authors conclude that the study helps identify genomic factors shaping TR mutagenesis, which they describe as still mysterious. They suggest that combining long-read sequencing with new software tools can be used to comprehensively investigate what influences TR mutation.
What the researchers tested
The researchers used PacBio HiFi long-read sequencing to profile nearly eight million TR loci in 28 members of a large four-generation CEPH/Utah family, called K1463. They identified de novo TR expansions and contractions across 20 children in the pedigree and examined features associated with these mutations.
What worked and what didn't
The study identified 1,270 de novo TR expansions and contractions. It also found 43 hyper-mutable TR loci, some of which expanded or contracted up to twelve times across the pedigree; at one locus, multiple variable number of tandem repeat (VNTR) motifs were present, but only one motif mutated recurrently across generations. The mutable motif differed from the next most common motif by just two base pairs.
What to keep in mind
The abstract does not describe broader limitations beyond the fact that the work was conducted in one large family pedigree. The findings are based on the K1463 family and the specific TR loci analyzed there.
Key points
- De novo tandem repeat mutations were more likely at longer loci with uninterrupted motifs and parental heterozygosity.
- Children born to older fathers had more de novo short tandem repeat mutations.
- The study identified 1,270 de novo tandem repeat expansions and contractions in 20 children.
- Forty-three tandem repeat loci were hyper-mutable in the K1463 pedigree.
- At one locus with multiple VNTR motifs, only one motif repeatedly mutated across generations.
Disclosure
- Research title:
- Genomic factors linked to tandem repeat mutability
- Authors:
- Thomas A. Sasani, Michael E. Goldberg, Akshay Kumar Avvaru, Thomas Nicholas, Deborah W. Neklason, Egor Dolzhenko, Tom Mokveld, Katherine M. Munson, Kendra Hoekzema, Marcelo Ayllon, Eli J. Kaufman, David Porubský, Paul N. Valdmanis, Evan E. Eichler, Aaron R. Quinlan, Harriet Dashnow
- Institutions:
- University of Utah, University of Colorado Anschutz Medical Campus, Pacific Biosciences (United States), University of Washington, University of Washington Medical Center, European Molecular Biology Laboratory, Howard Hughes Medical Institute
- Publication date:
- 2026-03-09
- OpenAlex record:
- View
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