Overlapping Xq13.3 duplications define an X-linked hypotrichosis simplex and implicate TAB3 dosage sensitivity.

Overlapping Xq13.3 duplications increase TAB3 dosage, causing X-linked hypotrichosis simplex with a 3.4 Mb critical region.

• Why it matters: Understanding the genetic basis of hereditary hair loss can improve diagnosis and treatment options for affected individuals, especially in X-linked cases.
• What they did: Researchers analyzed three families with X-linked hypotrichosis, identified duplications at Xq13.3, and examined gene expression and functional effects using mouse and keratinocyte models.
• The result: Increased TAB3 levels were linked to hair loss through impaired NF-κB signaling, and anti-inflammatory treatments showed potential to improve hair density, highlighting a new pathogenic pathway.