ABSTRACT
The human orosomucoid 1 gene (ORM1) codes an alpha-1-acid glycoprotein that has been classified as an acute-phase reactive protein, and a major drug-binding serum component, as well as an immunomodulatory protein with genetic polymorphisms. Evaluation of ORM variation through isoelectric focusing and immunobloting has revealed a world-wide distribution of the ORM1 F and ORM1 S alleles. We evaluated and examined the genetic characteristicsof two Mexican populations that have different anthropological and cultural antecedents, examining two ORM1 genotypes (exon 1 - A/G (Gln20Arg) and exon 5 G/A (Val156Met)) in 145 individuals, using nested polymerase chain reaction, sequencing, and restrited fragment length polymorphism. Mexican Mestizos had higher frequencies of the exon 1 A allele (P = 0.020) and AA genotype(P = 0.018) and lower frequency of the G allele (P = 0.020) when compared to Teenek Amerindians. When we examined exon 5 G/A (Val156Met) polymorphisms, we found significantly higher frequencies of the G allele (P = 0.0007) and the GG genotype (P = 0.0003) in the Mexican Mestizo population. The Teenek population had a significantly higher frequency of the A allele than has been reported for Chinese and African (P < 0.05) populations, and the G/A genotype was more frequently found in this Mexican population than in Chinese, African and European populations (P < 0.05).
Subject(s)
Humans , Exons/genetics , Genetics, Population , Indians, North American/genetics , Orosomucoid/genetics , Polymorphism, Genetic , Alleles , DNA , Gene Frequency , Genetic Variation , Mexico , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Sequence Analysis, DNA , Statistics as TopicABSTRACT
AIM OF THE STUDY: Microalbuminuria is currently the only diagnostic tool available for early diagnosis of diabetic nephropathy. The test is based on immunological detection of small quantities of albumin in the urinary samples of diabetes patients. There are several limitations of the use of microalbuminuria as an index of renal function. It is therefore desirable to identify additional protein markers that would augment prediction of diabetic nephropathy. The aim of this study is to identify urinary protein markers for specific and more accurate prediction of nephropathy in diabetes patients. DESIGN: 100 registered Type II diabetic patients were studied. Abundant proteins of microalbuminuria positive urinary samples of these patients were analyzed by proteomics approaches of 2-Dimentional Gel Electrophoresis (2DGE) and mass spectrometry. RESULTS: 2-DGE analysis of the urine sample revealed four main proteins along with albumin in these samples. These were zinc alpha-2 glycoprotein, alpha-1 acid glycoprotein, alpha-1 microglobulin and IgG as identified by Matrix Assisted Laser Desorption Ionization-Tune of Flight (MALDI-ToF) and by western blot. Twenty control samples and three cases with microalbuminuria negative to positive transition does suggest the early and co-appearance of the markers with albumin. We have also analyzed full length spectrum of these samples by MALDI-ToF. CONCLUSION: Our study shows the presence of additional proteins in urine samples of microalbuminuria positive diabetes patients. These proteins can be used as markers for specific and accurate clinical analysis of Diabetic nephropathy. We propose a mass spectrometry based high throughput diagnostic approach to detect these markers in the urine sample.
Subject(s)
Adult , Alpha-Globulins/genetics , Biomarkers/urine , Carrier Proteins/genetics , Diabetic Nephropathies/diagnosis , Glycoproteins/genetics , Humans , Middle Aged , Orosomucoid/genetics , Proteinuria/diagnosisABSTRACT
Human alpha(1)-acid glycoprotein (AGP) or orosomucoid (ORM) is a major acute phase protein that is thought to play a crucial role in maintaining homeostasis. Human AGP is the product of a cluster of at least two adjacent genes located on HSA chromosome 9. Using a range of restriction endonucleases we have investigated DNA variation at the locus encoding the AGP genes in a group of healthy Caucasians. Polymorphisms were identified using BamHI, EcoRI, BglII, PvuII, HindIII, TaqI and MspI. Nonrandom associations were found between the BamHI, EcoRI and BglII RFLPs. The RFLPs detected with PvuII, TaqI and MspI were all located in exon 6 of both AGP genes. The duplication of an AGP gene was observed in 11 of the individuals studied and was in linkage disequilibrium with the TaqI RFLP. The identification and characterization of these polymorphisms should prove useful for other population and forensic studies