Iminoglycinuria is a metabolic disorder resulting from defective renal tube reabsorption of proline, hydroxyproline and glycine. The prevalence is estimated at around 1 in 15 000. The disorder is usually asymptomatic and is identified fortuitously by detection of increased levels of the imino acids and glycine in the urine. It is transmitted as an autosomal recessive trait.

Anteriorly-facing nostrils viewed with the head in the Frankfurt horizontal and the eyes of the observer level with the eyes of the subject. This gives the appearance of an upturned nose (upturned nasal tip).