Pathology (G protein diseases)

A. Defective signal termination - signal excessive

 cholera
 adenoma of the pituitary (G-s-alpha)
 adenoma of the thyroid (G-s-alpha)
 adenoma of the adrenals (G-i2-alpha)
 adenoma of the ovary (G-i2-alpha)
 McCune-Albright syndrome (G-s-alpha)

B. Absent or inactive G-alpha - signal deficient

 pseudohypoparathyroidism type Ia (G-s-alpha)
 pseudohypoparathyroidism type Ib (G-s-alpha)
 night blindness (G-t-alpha)

C. Abnormal signal initiation - inadequate or excessive signal

 pertussis (G-i-alpha)
 pseudo hypoparathyroidism type Ia (G-s-alpha)
 testotoxicosis with pseudohypoparathyroidism type Ia (G-s-alpha)
 essential hypertension (beta3)

References

 Farfel Z, Bourne HR, Iiri T. The expanding spectrum of G protein diseases. N Engl J Med. 1999 Apr 1;340(13):1012-20. PMID: #10099144#