Candidate disease susceptibility genes include those encoding the MHC class II antigens, HLA-DR, -DQ, and -DP, and we have recently described an HLA-DQB1 association in IgAN.
These results suggest that HLA-DP region genes are not important in conferring disease susceptibility to IgAN and do not influence clinical disease expression.
We have therefore examined restriction fragment length polymorphisms (RFLPs) of the DP alpha and DP beta chain genes (DPA1 and DPB1 respectively) in IgAN, and have studied three caucasoid populations (North, Mid, Southern Europe) to determine whether ethnic variation in genetic susceptibility exists.
These findings indicate that abnormally regulated PCNA expression in PBMC may play an important role in the progression of IgA nephropathy, and that PCNA expression in PBMC may be a useful indicator of disease activity.
Their findings include the following: (1) partial deficiencies for C2, beta 1H (H), properdin (P), or C4 binding protein (C4BP) in four patients with end-stage renal disease, (2) an association between the C3*F allele with IgA nephropathy in the combined group of unrelated patients from Kentucky and the Mid-South, (3) the occurrence of C4B deficiency in two siblings with IgA nephropathy, and (4) an association between C4A deficiency and poor outcome in patients with IgA nephropathy diagnosed as adults.
Their findings include the following: (1) partial deficiencies for C2, beta 1H (H), properdin (P), or C4 binding protein (C4BP) in four patients with end-stage renal disease, (2) an association between the C3*F allele with IgA nephropathy in the combined group of unrelated patients from Kentucky and the Mid-South, (3) the occurrence of C4B deficiency in two siblings with IgA nephropathy, and (4) an association between C4A deficiency and poor outcome in patients with IgA nephropathy diagnosed as adults.
Their findings include the following: (1) partial deficiencies for C2, beta 1H (H), properdin (P), or C4 binding protein (C4BP) in four patients with end-stage renal disease, (2) an association between the C3*F allele with IgA nephropathy in the combined group of unrelated patients from Kentucky and the Mid-South, (3) the occurrence of C4B deficiency in two siblings with IgA nephropathy, and (4) an association between C4A deficiency and poor outcome in patients with IgA nephropathy diagnosed as adults.
The two closely linked genes are located on chromosome 6p, between HLA-B and -DR. Several reports have established complete C4B deficiency as the major genetic risk factor for IgA nephropathy (RR = 6.5; p = 0.0004).
Since angiotensin II is thought to play an important role in the evolution of renal disease in general, we tested whether genotype distribution of the I/D polymorphism is also different in patients with immunoglobulin A-glomerulonephritis (IgA-GN).
The results indicate that deletion polymorphism in the ACE gene, particularly the homozygote DD, is a risk factor for progression to chronic renal failure in IgA nephropathy.
We examined restriction fragment length polymorphisms (RFLPs) of the switch region genes of the IgM (S mu) and IgA1 (S alpha 1) heavy chain in 78 Japanese children with IgA nephropathy and 88 normal Japanese controls.
We studied a large North American Caucasian population of patients with biopsy proven IgA nephropathy for polymorphisms of HLA-A,B,C, HLA-DR, HLA-DQ and HLA-DP using a combination of serologic phenotyping and polymerase chain reaction sequence specific oligonucleotide probe (PCR-SSOP) hybridization genotyping.