Definition A condition (OMIM:146520) characterised by less than the normal amount of hair and early-onset hair loss. Scalp-limited hair loss begins by age 5 and progresses to nearly complete baldness by early adulthood. Body hair, beard, eyebrows, axillary hair, teeth, and nails develop normally.
Molecular pathology Defects of CDSN, which encodes a protein critical for maintaining the integrity of the epidermal barrier, cause hypotrichosis 2.
Synonyms Hypotrichosis simplex of the scalp, hypotrichosis–Spanish type