PTH and pseudohypoparathyroidism type 1A: PHP type−I (PHP−I), a term used to describe a condition in patients who show a blunted nephrogenous cAMP response to exogenously administered bioactive PTH, can be further classified into three different subtypes based on the presence of additional endocrine abnormalities, deficiency of the α−subunit of the stimulatory G protein (Gsα), and dysmorphic features of AHO (1).