Laboratory for Molecular Diagnostics
Center for Nephrology and Metabolic Disorders

Early pathway complement deficiencies

Deficiencies in complement components of the early classical pathway of complement activation are characterized by a predisposition to develop autoimmune disease. The factors involved are C1q, C1r, C1s, C2, C4.

Systematic

Hereditary complement disorders
CR1 deficiency
Complement C2 deficiency
Complement C3 deficiency
Complement C5 deficiency
Complement C6 deficiency
Complement C7 deficiency
Complement C8 deficiency
Complement C9 deficiency
Complement component C4 deficiency
Complement factor D deficiency
Complement factor I deficiency
Early pathway complement deficiencies
Complement component C1q deficiency
C1QA
C1QB
C1QC
Complement component C1r/C1s deficiency
C1R
Complement component C1s deficiency
C1S
Hereditary Angioedema
Properdin deficiency, X-linked
Terminal pathway complement deficiencies
Thrombotic microangiopathies

References:

1.

Boteva L et al. (2012) Genetically determined partial complement C4 deficiency states are not independent risk factors for SLE in UK and Spanish populations.

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2.

Braun L et al. (1990) Null alleles of human complement C4. Evidence for pseudogenes at the C4A locus and for gene conversion at the C4B locus.

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3.

Welch TR et al. (1990) Uniparental isodisomy 6 associated with deficiency of the fourth component of complement.

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4.

Partanen J et al. (1989) Determination of deletion sizes in the MHC-linked complement C4 and steroid 21-hydroxylase genes by pulsed-field gel electrophoresis.

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5.

Partanen J et al. (1988) C4 null phenotypes among lupus erythematosus patients are predominantly the result of deletions covering C4 and closely linked 21-hydroxylase A genes.

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6.

Awdeh ZL et al. (1981) Genetic analysis of C4 deficiency.

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7.

Barba G et al. (1993) Genetic basis of human complement C4A deficiency. Detection of a point mutation leading to nonexpression.

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8.

Wolski KP et al. (1976) Genetic linkage between the HL-A system and a deficit of the second component (C2) of complement in four generations of a family.

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9.

Johnson CA et al. (1992) Molecular heterogeneity of C2 deficiency.

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10.

Johnson CA et al. (1992) Type I human complement C2 deficiency. A 28-base pair gene deletion causes skipping of exon 6 during RNA splicing.

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11.

None (1986) Primary structure of human complement component C2. Homology to two unrelated protein families.

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12.

Dunham I et al. (1987) Molecular mapping of the human major histocompatibility complex by pulsed-field gel electrophoresis.

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13.

Bentley DR et al. (1984) Isolation of cDNA clones for human complement component C2.

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14.

Wetsel RA et al. (1996) Type II human complement C2 deficiency. Allele-specific amino acid substitutions (Ser189 > Phe; Gly444 > Arg) cause impaired C2 secretion.

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15.

D'Cruz D et al. (1992) Complement factor 2 deficiency: a clinical and serological family study.

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16.

None (1960) Essential hypocomplementemia: report of a case.

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17.

Simon S et al. (1991) A restriction fragment of the C2 gene is a unique marker for C2 deficiency and the uncommon C2 allele C2*B (a marker for type 1 diabetes).

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18.

None (1968) Inherited c'2 deficiency in man: lack of immunochemically detectable c'2 protein in serums from deficient individuals.

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19.

Böttger EC et al. (1986) Guinea pigs with inherited deficiencies of complement components C2 or C4 have characteristics of immune complex disease.

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20.

Cole FS et al. (1985) The molecular basis for genetic deficiency of the second component of human complement.

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21.

Callen JP et al. (1987) Subacute cutaneous lupus erythematosus in multiple members of a family with C2 deficiency.

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22.

Efthimiou J et al. (1986) Heterozygous C2 deficiency associated with angioedema, myasthenia gravis, and systemic lupus erythematosus.

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23.

Klemperer MR et al. (1966) Hereditary deficiency of the second component of complement (C'2) in man.

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24.

Ruddy S et al. (1970) Inherited abnormalities of the complement system in man.

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25.

None (1967) Inborn errors of the complement system of man.

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26.

Colten HR et al. (1981) Genetics and biosynthesis of complement proteins.

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27.

Provost TT et al. (1983) Homozygous C2 deficiency, lupus erythematosus, and anti-Ro (SSA) antibodies.

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28.

McCarty DJ et al. (1981) Serologic studies in a family with heterozygous C2 deficiency.

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29.

Belin DC et al. (1980) Familial discoid lupus erythematosus associated with heterozygote C2 deficiency.

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30.

Riggs JE et al. (1980) Heterozygous C2-deficiency and myasthenia gravis.

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31.

Mortensen JP et al. (1980) Studies on the C2-deficiency gene in man.

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32.

Thong YH et al. (1980) Homozygous deficiency of the second component of complement presenting with recurrent bacterial meningitis.

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33.

Awdeh ZL et al. (1981) Complement-human histocompatibility antigen haplotypes in C2 deficiency.

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34.

Lhotta K et al. (1990) Renal disease in a patient with hereditary complete deficiency of the fourth component of complement.

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35.

Vergani D et al. (1985) Genetically determined low C4: a predisposing factor to autoimmune chronic active hepatitis.

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36.

Ranford P et al. (1987) A high frequency of inherited deficiency of complement component C4 in Darwin Aborigines.

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37.

Huang DF et al. (1995) Population and family studies of three disease-related polymorphic genes in systemic lupus erythematosus.

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Update: April 29, 2019