Association between RAPH1 Gene Haplotypes and CHE2 Locus Phenotypes.

The human butyrylcholinesterase (BChE) is a serum esterase that has been associated with body mass index (BMI) and obesity. Its activity is conditioned by alleles of BCHE gene and the CHE2 locus that codifies an unknown BChE-binding protein (C5 complex). The hypothesis that the CHE2 locus is the RAPH1 gene, which encodes lamellipodin (Lpd), was raised in a study that observed Lpd peptides released from denatured BChE tetramers. The aim of this study was to test this hypothesis by evaluating SNPs of RAPH1 gene (rs2246118:C > T, rs3814365:A > G and rs2465520:C > T) in 34 CHE2 C5+ and 92 CHE2 C5- individuals, corresponding to the presence and absence of C5 complex. The results showed association of two haplotypes (CAC and TGC) with CHE2 C5+ phenotype. RAPH1 haplotypes was also associated with intense (TGC) and faint (CAC) CHE2 C5+ phenotypes. BChE activity was higher in intense CHE2 C5+ than faint CHE2 C5+ phenotype. Our results corroborate the hypothesis that the RAPH1 gene is the CHE2 locus and suggest that the variable expressivity of the CHE2 C5+ phenotypes is, at least in part, due to its genetic heterogeneity, which is leading to increased BChE activity only in individuals with intense CHE2 C5+ phenotype.

Gestational diabetes mellitus (GDM) decreases butyrylcholinesterase (BChE) activity and changes its relationship with lipids.

Many conditions interfere with butyrylcholinesterase (BChE) activity, e.g., pregnancy or presence of the BCHE gene variant -116A can decrease activity whereas obesity and types I and II diabetes mellitus can increase activity. In this study, we examined BChE activity, -116A and 1615A BCHE gene variants, and anthropometric and biochemical variables associated with diabetes in patients with gestational diabetes mellitus (GDM) and in healthy pregnant women. BChE activity was measured spectrophotometrically using propionylthiocholine as substrate and genotyping of the -116 and 1615 sites of the BCHE gene was done with a TaqMan SNP genotyping assay. Three groups were studied: 150 patients with GDM, 295 healthy pregnant women and 156 non-pregnant healthy women. Mean BChE activity was significantly lower in healthy pregnant women than in women from the general population and was further reduced in GDM patients. BChE activity was significantly reduced in carriers of -116A in GDM patients and healthy pregnant women. Although GDM patients had a significantly higher mean body mass index (BMI) and triglycerides than healthy pregnant women, they had lower mean BChE activity, suggesting that the lowering effect of GDM on BChE activity was stronger than the characteristic enhancing effect of increased BMI and triglycerides.

Investigation of Association between Susceptibility to Leprosy and SNPs inside and near the BCHE Gene of Butyrylcholinesterase.

Leprosy is a chronic disease caused by Mycobacterium leprae and affects the skin and the peripheral nervous system. Butyrylcholinesterase is coded by the BCHE gene, and the atypical allele (70G; rs1799807) has been investigated as a leprosy risk factor, with conflicting results. The present study estimated the frequencies of variants of rs1799807 and of five additional SNPs at the BCHE gene or near it: rs1126680, rs1803274, rs2863381, rs4440084, and rs4387996. A total of 167 patients and 150 healthy controls were genotyped by TaqMan PCR. Significantly higher allelic (70G) and genotypic (70DG) frequencies in rs1799807 were found in the patient group, with odds ratio (OR) of 6.33 (1.40 to 28.53) for the heterozygote. This finding was replicated in a comparison of the cases against a control group of 361 blood donors. The present data suggest that the atypical BChE variant may predispose to leprosy per se.

Obesity and variants of the GHRL (ghrelin) and BCHE (butyrylcholinesterase) genes.

Ghrelin coded by the GHRL gene is related to weight-gain, its deactivation possibly depending on its hydrolyzation by butyrylcholinesterase (BChE) encoded by the BCHE gene, an enzyme already associated with the body mass index (BMI). The aim was to search for relationships between SNPs of the GHRL and BCHE genes with BChE activity, BMI and obesity in 144 obese and 153 nonobese Euro-Brazilian male blood donors. In the obese individuals, a significant association with higher BChE activity, in the 72LM+72MM; -116GG genotype class (GHRL and BCHE genes, respectively) was noted. No significant differences were found otherwise, through comparisons between obese and control individuals, of genotype and allele frequencies in SNPs of the GHRL gene (Arg51Gln and Leu72Met), or mean BMI between 72LL and 72LM+72MM genotypes. Although there appears to be no direct relationship between the examined GHRL SNPs and BMI, the association of the 72M SNP with higher BChE activity in obese subjects probably points to a regulatory mechanism, thereby implying the influence of the GHRL gene on BChE expression, and a consequential metabolic role in the complex process of fat utilization.

Obesity and variants of the GHRL (ghrelin) and BCHE (butyrylcholinesterase) genes

Ghrelin coded by the GHRL gene is related to weight-gain, its deactivation possibly depending on its hydrolyzation by butyrylcholinesterase (BChE) encoded by the BCHE gene, an enzyme already associated with the body mass index (BMI). The aim was to search for relationships between SNPs of the GHRL and BCHE genes with BChE activity, BMI and obesity in 144 obese and 153 nonobese Euro-Brazilian male blood donors. In the obese individuals, a significant association with higher BChE activity, in the 72LM+72MM; -116GG genotype class (GHRL and BCHE genes, respectively) was noted. No significant differences were found otherwise, through comparisons between obese and control individuals, of genotype and allele frequencies in SNPs of the GHRL gene (Arg51Gln and Leu72Met), or mean BMI between 72LL and 72LM+72MM genotypes. Although there appears to be no direct relationship between the examined GHRL SNPs and BMI, the association of the 72M SNP with higher BChE activity in obese subjects probably points to a regulatory mechanism, thereby implying the influence of the GHRL gene on BChE expression, and a consequential metabolic role in the complex process of fat utilization.

Amplification and deletion of the ACHE and BCHE cholinesterase genes in sporadic breast cancer.

Increasing evidence supports the involvement of acetylcholinesterase and butyrylcholinesterase in cell proliferation control and differentiation, reinforcing the hypothesis that these enzymes might have an influence in tumorigenesis. It has already been shown that the cholinesterase genes are structurally altered or aberrantly expressed in a variety of tumor types. In this study, amplifications and deletions in the ACHE and BCHE genes were investigated in sporadic breast tumors using real-time polymerase chain reaction and the relative quantification method. The majority of the tumor tissues showed a notable number of both deletions and amplifications: 65.7% and 22.9%, respectively, in BCHE and 45.7% and 31.4%, respectively, in ACHE. Deletion of the ACHE gene was significantly correlated with amplification of the protooncogene ERBB2. Tumor size was significantly higher when the ACHE gene was amplified, and the total number of alterations (amplifications plus deletions) of the BCHE gene was positively correlated with tumor malignancy grade.

Molecular forms of butyrylcholinesterase and obesity.

This study compared obese (N = 134) and unobese (N = 92) male blood donors, regarding the relative intensity (RI) and activity of different molecular forms (G1, G2, G4 and G1-ALB) of butyrylcholinesterase (BChE, EC 3.1.1.8) found in plasma, thereby searching for an association between these variables with obesity and SNPs of exons 1 and 4 of the BCHE gene. It was shown that obese and unobese individuals do not differ in the RI of each BChE band, even when classifying the sample into three genotypes of exons 1 and 4 of the BCHE gene (-116GG/539AA, -116GG/539AT, -116GA/539AT). Although the mean BChE activity of each band was significantly higher in obese than in unobese blood donors, the proportions of BChE bands were maintained, even under the metabolic stress associated to obesity, thereby leading to infer that this proportion is somehow regulated, and may therefore be important for BChE functions.

Molecular forms of butyrylcholinesterase and obesity

This study compared obese (N = 134) and unobese (N = 92) male blood donors, regarding the relative intensity (RI) and activity of different molecular forms (G1, G2, G4 and G1-ALB) of butyrylcholinesterase (BChE, EC 3.1.1.8) found in plasma, thereby searching for an association between these variables with obesity and SNPs of exons 1 and 4 of the BCHE gene. It was shown that obese and unobese individuals do not differ in the RI of each BChE band, even when classifying the sample into three genotypes of exons 1 and 4 of the BCHE gene (-116GG/539AA, -116GG/539AT, -116GA/539AT). Although the mean BChE activity of each band was significantly higher in obese than in unobese blood donors, the proportions of BChE bands were maintained, even under the metabolic stress associated to obesity, thereby leading to infer that this proportion is somehow regulated, and may therefore be important for BChE functions.

Ectodermal dysplasias: clinical and molecular review.

Ectodermal dysplasias (EDs) as defined by Freire-Maia [Freire-Maia (1971); Hum Hered 21: 309-312; Freire-Maia (1977); Acta Genet Med Gemellol 26: 121-131] are congenital disorders characterized by alterations in two or more ectodermal structures, at least one of these involving alterations in hair, teeth, nails, or sweat glands. Suggestions for a new definition and, consequently, for a new classification of EDs have being proposed lately, mainly with the purpose of connecting clinical knowledge with recent discoveries of gene mutations responsible for about 30% of EDs. The aim of this review was to update the clinical classification of EDs with recent molecular (64 genes and 3 chromosome regions) and clinical data, mainly of EDs of the A group (N = 186), in order to contribute information for the evaluation of the ED definition proposed by Freire-Maia. Our conclusion is that the combination of both procedures-clinical and molecular-only brings advantages for a deeper knowledge of EDs. First, it allows a rapid diagnosis that may become even more precise whenever DNA exams are available. Secondly, the comprehension of the biological mechanisms that cause EDs is needed for the design of efficient prevention and treatment approaches.

Association of variants of the -116 site of the butyrylcholinesterase BCHE gene to enzyme activity and body mass index.

Butyrylcholinesterase (BChE) is coded by the BCHE gene that presents four exons. The non-codifying exon 1 presents two variants -116G and -116A, being -116A preferentially in cis conformation with the 539T variant (K) of exon 4 which was associated with lower BChE activity and lower body mass index (BMI) variance. This study analyzed the frequency of -116 variants and the relation of genotypes -116GG;539AA, -116GG;539AT and -116GA;539AT with BChE activity and with BMI in Euro-Brazilian blood donors. The frequency of -116A was significantly higher (18.9%) in the low BChE activity group when compared to obese (8.6%) and normal BMI (9.3%) groups. In obese and non-obese groups, the -116GA;539AT genotype showed significantly lower mean BChE activity when compared to the -116GG;539AA genotype and in obese individuals the -116GA;539AT genotype also showed lower BChE activity than the -116GG;539AT genotype. In a sample selected independently of BMI, the -116GA;539AT genotype showed significantly higher BMI variance (21.75) when compared to -116GG;539AA (12.14) and to -116GG;539AT (13.43) genotypes, indicating that the association with higher BMI variance only occurs in the presence of the -116A variant. In the obese sample, the -116GG;539AT genotype presented mean (32.1+/-0.3) and variance (2.3) of BMI significantly lower than those found in the -116GG;539AA (33.0+/-0.3 and 9.9, respectively) and -116GA;539AT (33.7+/-0.7 and 12.2, respectively) genotypes. These data show that: (1) the K (539T) variant alone is not associated with decreased BChE activity, being the 5' UTR -116A variant necessary for this decrease, probably by affecting transcription and/or translation of the BCHE gene; (2) samples with different BMI distributions present different relationships between BCHE genotypes and BMI, reinforcing the hypothesis of a role for the BCHE gene in BMI determination.

Two new mutations of the human BCHE gene (IVS3-14T>C and L574fsX576).

The genetic variation of human butyrylcholinesterase is associated with the majority of prolonged cases of apnea in patients submitted to the muscle relaxant succinylcholine. The present study reports two new mutations of the BCHE gene in 346 Euro-Brazilians: IVS3-14T>C found in five heterozygotes (allele frequency: 0.72+/-0.32%) and L574fsX576 found in one heterozygote (allele frequency: 0.14+/-0.14%). These two variants were not found in 85 Guarani Amerindians. It is not expected that the IVS3-14T>C mutation may interfere in the splicing process and that the mutation found in exon 4 (L574fsX576) may disturb BChE tetramerization and activity.

[Prevalence of hemoglobin S in the State of Paraná, Brazil, based on neonatal screening]. / Prevalência da hemoglobina S no Estado do Paraná, Brasil, obtida pela triagem neonatal.

The Brazilian Ministry of Health created the National Neonatal Screening Program under ruling no. 822/2001, including neonatal screening for hemoglobinopathies. In the State of Paraná, neonatal screening is conducted by the Ecumenical Foundation for the Protection of the Handicapped. The prevalence rates were determined for homozygous and heterozygous hemoglobin S and Sbeta-thalassemia. Blood samples drawn on filter paper were examined by isoelectric focusing (IEF) and high-performance liquid chromatography (HPLC). From January 2002 to December 2004, 548,810 newborns were screened, with the detection of 21 with FS, two FSA/FS, and four FSA. After confirmatory tests at six months of age, 12 were defined as sickle-cell anemia, or a prevalence of 2.2:100,000 newborns; Sbeta-thalassemia was confirmed in 15 (2.7:100,000 newborns); and 8,321 newborns were diagnosed as heterozygous HbS (1,500:100,000 newborns). HbS prevalence in Paraná (in southern Brazil) is lower than in the Central-West, North, and Northeast of the country. Ethnic origin of the population, fetal deaths, and non-random procreation may contribute to the relatively low number of homozygous individuals in the State. Sbeta-thalassemia interaction suggests the presence of Euro-Mediterranean peoples in this population's miscegenation.

Prevalência da hemoglobina S no Estado do Paraná, Brasil, obtida pela triagem neonatal / Prevalence of hemoglobin S in the State of Paraná, Brazil, based on neonatal screening

O Ministério da Saúde instituiu o Programa Nacional de Triagem Neonatal através da Portaria nº. 822/GM, incluindo a pesquisa das hemoglobinopatias nos recém-nascidos. No Paraná, é realizada pela Fundação Ecumênica de Proteção ao Excepcional. Determinou-se a prevalência da hemoglobina S em homozigose, heterozigose e Sbeta-talassemia no estado. O sangue coletado em papel filtro foi examinado por focalização isoelétrica e cromatografia líquida de alta precisão (HPLC). De janeiro de 2002 a dezembro de 2004, foram triados 548.810 recém-nascidos e detectados 21 recém-nascidos com os resultados FS, dois FSA e/ou FS e quatro FSA. Após exames confirmatórios aos seis meses de idade, 12 foram definidos como anemia falciforme, com prevalência de 2,2:100 mil recém-nascidos; a interação Sbeta-talassemia foi confirmada em quinze (2,7:100 mil recém-nascidos); e 8.321 recém-nascidos foram diagnosticados como heterozigotos para HbS (1.500:100 mil recém-nascidos). A prevalência da HbS no Paraná é menor do que nas regiões Centro-Oeste, Norte e Nordeste do país. Origem étnica da população, óbitos fetais e casamentos preferenciais podem estar contribuindo para não haver maior número de homozigotos no estado. A interação Sbeta-talassemia sugere presença de povos euro-mediterrâneos na miscigenação dessa população.

The Brazilian Ministry of Health created the National Neonatal Screening Program under ruling no. 822/2001, including neonatal screening for hemoglobinopathies. In the State of Paraná, neonatal screening is conducted by the Ecumenical Foundation for the Protection of the Handicapped. The prevalence rates were determined for homozygous and heterozygous hemoglobin S and Sbeta-thalassemia. Blood samples drawn on filter paper were examined by isoelectric focusing (IEF) and high-performance liquid chromatography (HPLC). From January 2002 to December 2004, 548,810 newborns were screened, with the detection of 21 with FS, two FSA/FS, and four FSA. After confirmatory tests at six months of age, 12 were defined as sickle-cell anemia, or a prevalence of 2.2:100,000 newborns; Sbeta-thalassemia was confirmed in 15 (2.7:100,000 newborns); and 8,321 newborns were diagnosed as heterozygous HbS (1,500:100,000 newborns). HbS prevalence in Paraná (in southern Brazil) is lower than in the Central-West, North, and Northeast of the country. Ethnic origin of the population, fetal deaths, and non-random procreation may contribute to the relatively low number of homozygous individuals in the State. Sbeta-thalassemia interaction suggests the presence of Euro-Mediterranean peoples in this population's miscegenation.

Five new naturally occurring mutations of the BCHE gene and frequencies of 12 butyrylcholinesterase alleles in a Brazilian population.

Human butyrylcholinesterase (BChE; EC 3.1.1.8) is codified by the BCHE gene (3q26.1-q26.2) in which 65 variants have been identified. BChE is a scavenger of organophosphorus and carbamate compounds and hydrolyzes succinylcholine, mivacurium and cocaine. The present study describes 12 naturally occurring BCHE mutations including five new mutations (K12R, G15G, V294M, G333C and R470W) identified in 366 blood donors from Southern Brazil. Exons 2 and 4 of the BCHE gene were examined by PCR-SSCA and samples with unexpected electrophoretic patterns were sequenced. The respective nucleotide substitution that characterizes each of the four new nonsynonymous mutations was introduced into BCHE cDNA by site directed mutagenesis and transfected into human embryonic kidney 293T cells and/or Chinese hamster ovary cells. The catalyzed hydrolysis of butyrylthiocholine (BTC) by BChE was measured by the Ellman method. Enzyme kinetic parameters obtained after the expression of the respective recombinant BChE evaluated the effects of the four nonsynonymous mutations. Thirty-four out of 366 individuals carried a BChE mutation in exon 2. The K variant mutation, A539T in exon 4, was present in one out of three persons. Gene expression showed that only one of the newly identified mutations (G333C) altered BChE activity, leading to a decrease of about 80% in relation to the wild-type enzyme.

Absence of the -116A variant of the butyrylcholinesterase BCHE gene in Guarani Amerindians from Mato Grosso do Sul

Butyrylcholinesterase (BChE; EC 3.1.1.8; Online Mendelian Inheritance in Man (OMIM) number 177400) is an enzyme found in many human tissues and encoded by the BCHE gene, of which 65 variants have been identified. In a recent study we found that the -116A variant of exon 1 of the BCHE gene was associated with lower mean BChE activity. The present study analyzed the -116 single nucleotide polymorphism (SNP) in 253 Guarani Amerindian Brazilians from the state of Mato Grosso do Sul (148 Guarani-Kaiowá, 83 Guarani-Ñandeva and 22 Kaiowá-Ñandeva descendants) and verified that they were all homozygotic for the -116G variant. A comparative analysis of the -116 site in nine vertebrate species indicated the -116A variant as the ancestral type. This is the first study of the -116 SNP in Amerindians and it is therefore difficult to infer whether or not the -116A variant was always absent from southern paleo-Amerindians or was present and then subsequently lost due to evolutionary factors.

Expression of three naturally occurring genetic variants (G75R, E90D, I99M) of the BCHE gene of human butyrylcholinesterase.

The present paper examined the effects of three non synonymous BCHE mutations (G75R, E90D and /99M) on enzyme kinetic parameters obtained after the expression of the respective recombinant BChEs. The respective nucleotide substitution that characterizes each of the three variants was introduced into BCHE cDNA by site directed mutagenesis and transfected into human embryonic kidney 293 T cells and Chinese hamster ovary cells (for E90D). BChE catalysed hydrolysis of butyrylthiocoline (BTC) was measured by Ellman method. The expression results showed that: (1) the activity of the G75R enzyme represents approximately 45% of the wild-type activity, whereas that of the I99M enzyme does not differ from the wild-type; (2) the E90D enzyme presents a silent phenotype; disruption of the salt bridge between E90 and R42 may cause the enzyme to be rapidly degraded inside the cells. In homozygous form the E90D enzyme may confer increased susceptibility to succinylcholine, but may delay cognitive impairment in aged individuals. BChE genotyping may become important for estimating prognosis, and the knowledge of the genetic variants of BChE in a particular population may be useful for carrying out the genotyping assays.

Butyrylcholinesterase genetic variability in Guarani Amerindians from the Brazilian state of Mato Grosso do Sul

Human butyrylcholinesterase (BChE; EC 3.1.1.8) is a polymorphic enzyme coded by the BCHE gene (3q26.1-q26.2) while the CHE2 gene (2q33-q35) determines a still not characterized substance that forms a complex with BChE (C5), being the CHE2 C5+ and CHE2 C5- phenotypes detected in electrophoresis. The present study investigated BCHE and CHE2 variability and the BChE activity of Brazilian Guarani Amerindians from the Kaiowá and Ñandeva sub-groups living in several indigenous territories in the Brazilian state of Mato Grosso do Sul. The frequency of the BCHE exon 2 D70G (A) allele was 0.60 percent ± 0.35 percent while that of the BCHE exon 2 G390V (F-2) allele, never before screened in Amerindians, was 8.82 percent ± 1.35 percent. This is the first time that the BCHE gene exon 4 A539T (K) allele has been surveyed in Brazilian Amerindians where it was found at a frequency of 3.69 percent ± 0.85 percent, similar to that found in Chilean Mapuche Amerindians. The BCHE gene variability seen in this survey differs from that of non-isolated populations in respect to both A539T and G390V allele frequency. The CHE2 C5+ phenotype frequency was 14.40 percent ± 2.22 percent and falls within the range of that found for other Brazilian Amerindian samples.