nt expressions and deletions
of the gene. Type I is characterized by no detectable C2 protein being synthesized.
There is a deletion in the 134 basepair single exon Johnson et al. (1992).
Exons are the part of the gene that are expressed, and the intron are the
part that are cut out. This deletion causes a frame shift in the chromosome.
The result of this shift is the generation of a termination codon, TGA,
16 basepairs downstream from the deletion Johnson et al. (1992). A 28 basepair
deletion is detected in the gene 9 basepairs from the 3-prime end of the
134 basepair exon. Type II has a lower than normal synthesis of the C2 protein
Johnson et al. (1992). There are two mutation detected in this type, they
are on exon 5 and exon 11 Johnson et al. (1992).
In conclusion, C2 deficiency is a disorder cause by a mutation in chromosome
6. This mutation causes impaired immunity against bacterial infection. A
person homozygous for C2 deficiency will have a more sever case of infections
than a person who is heterozygous for this deficiency. This deficiency is
a multifactorial trait that is often associated with other immune deficiencies.
Duby DP. Alper CA,;
Polymorphic Hh genes in the HLA-B© region control natural killer cell
frequency and activity Journal of Experimental medicine, 179 (4):1193-203,
1994 Apr 1.
Johnson, C.A.; Densen, P.; Hurford, R.K., Jr.; Colten, H.R.; Wetse, R.A.;
Type I human complement C2 deficiency: a 28-base pair gene deletion causes
skipping of exon 6 during RNA spicing, 1992.
Merralls, Stephanie.; Complement Deficiencies, 1995.
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