Generation of Hoxc13 knockout pigs recapitulates human ectodermal dysplasia-9

Area of Science:

• Genetics and Developmental Biology
• Dermatology
• Animal Models

Background:

• Atrichia and sparse hair, common in Ectodermal Dysplasia-9 (ED-9), cause significant patient distress.
• The Hoxc13 gene is implicated in ED-9, but existing mouse models exhibit severe phenotypes not seen in human ED-9 patients.
• There is a need for accurate animal models to study ED-9 pathogenesis and explore hair regeneration.

Purpose of the Study:

• To generate a pig model that accurately mimics the human ED-9 phenotype.
• To investigate the role of Hoxc13 in hair development and skin structure.
• To establish a novel preclinical model for ED-9 and hair regeneration research.

Main Methods:

• CRISPR/Cas9 and somatic cell nuclear transfer were used to create Hoxc13 gene knockout pigs.
• Single-stranded oligonucleotides (c.396C>A) were employed for precise gene editing.
• Phenotypic analysis included gene expression, hair follicle morphology, and overall physiological assessment.

Main Results:

• Three types of biallelic Hoxc13 mutations were generated in cloned piglets.
• Hoxc13 knockout pigs exhibited hypotrichosis and abnormal hair follicle development, mirroring ED-9.
• Crucially, these pigs showed normal skin structure, skeletal development, and growth, unlike mouse models.
• Downregulation of Hoxc13-regulated genes (Foxn1, Krt85, Krt35) was observed in the knockout pigs.

Conclusions:

• Hoxc13 knockout pigs provide a faithful model for studying Ectodermal Dysplasia-9.
• This hairless pig model is suitable for research into hair regeneration therapies.
• The model's normal physiology makes it valuable for broader dermatological research due to pig-human skin similarity.