Gene: [11q1/C1NH] complement component 1 inhibitor; hereditary angioneurotic edema, type II (HANE, C1 inhibitor deficiency); partial deficiency of complement component 4 (due to dysfunctional C1 inhibitor; MIM:120790); [HANE CINH ]

FUN

The protein product is a specific inhibitor of proteolytic activity of C1R and C1S complement subcomponents. It forms a covalent complex with them, that results in the dissociation of C1 component and blocks the activation of C4 and C2 components with active C1S. The complement component 1 inhibitor inhibits also other serine proteases (plasmin, kallikrein, coagulation factors XIA and XIIA)."

MOP

Complement component 1 inhibitor is the most glycosilated serum protein (contains up to 35 wt % of carbohydrate residues). It is synthesized in liver as a single polypeptide (MM 105 kD)."

FAG

The enzyme is a member of a large family of serine proteases (serpins) and shares homology (about 20%) with antithrombin III (GEM:01q23/AT3), alpha-1 antitrypsin (GEM:14q321/PI1), alpha-1 antichymotrypsin (GEM:14q321/AACT), and angiotensinogen (GEM:01q4/AGT)."

FOG

Angioneurotic edema is inherited as an autosomal dominant trait.

PHE

Heterozygosity for C1 inhibitor deficiency may manifest itself in one of two forms: HANE-1 (the activity of the structurally normal protein is decreased down to 20%) and HANE-2 (the level of the abnormal protein, which is unable to inhibit C1, increases up to 400%)."

PRO

The pC1INH1 probe contains a 0.6-kb PstI fragment of cDNA.

REF

MOP,PAT "Cicardi &: J Clin Invest, 79, 698-702, 1987a
POL "Cicardi &: J Clin Invest, 80, 1640-1643, 1987b
PRO,SEQ "Davis AE &: PNAS, 83, N10, 3161-3165, 1986
LOC,MOL "Theriault A &: Hum Genet, 84, N5, 477-479, 1990
MUT "Zahedi R &: J Clin Invest, 95, 1299-1305, 1995

KEY

imm, comp, hem, serp

CLA

coding, basic

LOC

11 q12-13.1

MIM

MIM: 106100

SYN

HANE CINH