A New York-based biotechnology startup has reported the successful generation of beagle puppies lacking the primary canine allergen through CRISPR-Cas9 gene editing. The work, detailed in a study published in The CRISPR Journal, targets Can f 1, a lipocalin protein secreted in saliva and deposited in dander that drives allergic responses in an estimated 15% of the human population. The resulting animals represent an early demonstration that precise genetic disruption of this allergen is compatible with normal canine development.
Researchers introduced a single-base insertion in exon 1 of the Can f 1 gene in primary canine fibroblasts, creating a frameshift mutation that abolished protein production. Whole-genome sequencing confirmed the absence of detectable off-target mutations or large-scale rearrangements. Gene-edited cells served as nuclear donors for somatic cell nuclear transfer; the resulting embryos were transferred to a surrogate beagle, yielding two healthy, genetically identical puppies born in September 2024.
Western blot analysis of saliva and dander extracts from the animals detected no residual Can f 1 protein, in contrast to high levels observed in control poodles and goldendoodles. Skin-prick testing further showed that extracts from the gene-edited dogs elicited no IgE-mediated response in a sensitized individual, while extracts from wild-type dogs produced strong reactions. The puppies, now approaching two years of age, have exhibited normal growth, physical development, and behavior, supporting the conclusion that Can f 1 is non-essential for host physiology. This approach differs from conventional allergy management strategies that modulate the human immune response and instead addresses allergenicity at its biological source in the animal. Parallel efforts have previously demonstrated CRISPR-based knockout of the major cat allergen Fel d 1.
In the future, expansion of the platform to additional dog breeds and secondary allergens, combined with regulatory clearance for genome-edited animals, could enable broader production of hypoallergenic companion and service dogs.
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