Hypertrichosis refers to a condition characterized by an atypical growth of too much hair. It may be localized, i.e. the hair growth over a certain body part. When hypertrichosis involves the entire body the condition is referred to as generalized hypertrichosis. It may also be congenital (at birth) or acquired (appears later in life). Synophrys is a localized hypertrichosis in between the eyebrows. This condition gives an appearance of a single long eyebrow (or unibrow). A unibrow (also called monobrow) is a seemingly single eyebrow due to the two eyebrows converging in the middle, above the nasal bridge. The hair in the middle has the same thickness and color as the two eyebrows. Having a unibrow is a recessive trait and recently was found to be associated with the gene, PAX3.1
Synophrys is one of the prominent features of individuals with Cornelia de Lange syndrome. Conversely, synophrys is also seen in individuals without such disorder. Other medical conditions associated with having unibrow are Patau syndrome, Waardenburg syndrome, and Gorlin syndrome.
Word origin: syn- from Greek sun ( together, with) + ophrys (eyebrow)
1 Adhikari, K. et al. (2016). A genome-wide association scan in admixed Latin Americans identifies loci influencing facial and scalp hair features. Nat Commun. 7:10815.