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G Lucotte

Publications and source records attributed to G Lucotte.

At least 55 records · Page 3Linked to original sources
PubMed1999

Origins of Falasha Jews studied by haplotypes of the Y chromosome.

DNA samples from Falasha Jews and Ethiopians were studied with the Y-chromosome-specific DNA probe p49a to screen for TaqI restriction polymorphisms and haplotypes. Two haplotypes (V and XI) are the most widespread in Falashas and Ethiopians, representing about 70% of the total number of haplotypes in Ethiopia. Because the Jewish haplotypes VII and VIII are not represented in the Falasha population, we conclude that the Falasha people descended from ancient inhabitants of Ethiopia who converted to Judaism.

Adult↗
PubMed1998

Distribution of the CCR5 gene 32-bp deletion in Europe.

The chemokine receptor CCR5 constitutes the major coreceptor for the macrophage-tropic strains of HIV-1. A mutant allele of the CCR5 gene called delta32 was shown to provide strong resistance to homozygotes against infection by HIV. The frequency of the delta32 allele was investigated in 2522 noninfected unrelated individuals from 16 different European populations. The delta32 allele was found in all populations studied, with a mean frequency of about 9.1%. A north-to-south gradient correlating latitude with delta32 allelic frequencies was found (r = 0.726), with highest allele frequencies in Denmark and Northern France, and the lowest allele frequencies in Corsica.

Alleles↗
PubMed1998

Frequency of the C282Y mutation of hemochromatosis in five French populations.

Hereditary hemochromatosis mutation 845A (C282Y) in the HFE gene was recently described, and the C282Y frequencies were reported for various world populations. The aim of this study was to determine the Y allele frequencies of the C282Y mutation for five French populations. The most elevated value (= 5.6%) was obtained for Bretons, in accordance to the hypothesis indicating a Celtic origin of the hereditary hemochromatosis mutation.

Adult↗
PubMed1998

Celtic origin of the C282Y mutation of hemochromatosis.

The C282Y mutation in the HFE gene is the main mutation causing hemochromatosis, and C282Y frequencies have been reported for various European populations. The aim of this review is to compile the Y allele frequencies of the C282Y mutation for twenty European populations. The most elevated value (6.88%) is observed in residual Celtic populations in UK and France, in accordance to the hypothesis of Simon et al. concerning a Celtic origin of the hereditary hemochromatosis mutation.

Europe↗
PubMed1998

ARMS test for diagnosis of factor V Leiden mutation and allele frequencies in France.

The authors have developed a simple and rapid amplification-refractory mutation system (ARMS) assay for the factor V Leiden mutation (MIM 227400.0001). Polymerase chain reaction (PCR) primers within exon 10 of the factor V gene were designed; one common upstream primer was paired with either a normal or a mutant-specific downstream primer. The assay was validated using factor V Leiden DNA samples of thrombophilic patients ascertained by the restriction enzyme cleavage method of reference. In the normal French population, allele frequencies of the factor V Leiden mutation are 2.6% for the Parisian region and 1.7% for the south of the country.

Alleles↗
PubMed1998

The use of nested RT-PCR of prostate-specific membrane antigen in blood cells: implications for the detection of haematogenous neoplastic cells in patients with prostate adenocarcinoma.

The aim of this study was to determine the presence of haematogenous neoplastic cells in patients with prostate cancer. Circulating prostate cells can be detected in cancer patients by using a nested-reverse transcriptase-polymerase chain reaction assay (RT-PCR), for prostate-specific membrane (PSM) antigen mRNA. This sensitive nested RT-PCR assay may play a crucial role in the administration of adjuvant therapy of patients with prostate adenocarcinoma.

Adenocarcinoma↗
PubMed1998

[Frequency of the coreceptor CCR5 gene delta 32 mutation in different French regions].

We studied the frequency of the coreceptor CCR5 gene delta 32 mutation on 1,836 DNA samples originating from ten French regions. This mutation confers, in the homozygous state, resistance to HIV-1 infection. For the whole territory, the mean percentage presence of the delta 32 mutation is 9.2%. The mutation is statistically more frequent in the north (11.2%) than in the south (6.3%) of the country; this differentiation corresponds probably to a gradient of decreasing frequencies of the delta 32 mutation in Europe.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Mutation analysis of the HLA-H gene in French hemochromatosis patients, and genetic counseling in families.

Mutation analysis of the HLA-H gene in French hemochromatosis patients and genetic counseling in families: Genotype analysis of 61 hemochromatosis patients living in France and 126 controls confirms that the disease is strongly associated with homozygosity for the mutation C282Y of the HLA-H gene: in our sample 67.2% patients, and none of the controls, carry two copies of the C282Y mutation; the frequency of the C282Y allele in a control population is 3.97%. A second variant (H63D) at the HLA-H gene is somehow more enriched (8.2%) in patient chromosomes that do not carry the C282Y mutation. The C282Y mutation was used in 10 hemochromatosis families for genetic counseling.

Amino Acid Substitution↗
PubMed1997

Detection of Borrelia burgdorferi DNA by polymerase chain reaction in urine specimens of patients with erythema migrans lesions.

A polymerase chain reaction (PCR) assay was developed for the detection of Borrelia burgdorferi-specific DNA in the urine of patients with erythema migrans (EM). The target for the PCR was a specific region of the flagellin gene, and DNA was extracted from urine by Chelex resin. The detection limit was 1-10 genomes of B. burgdorferi, B. garinii or B. afzelii. A prospective study was performed with 12 consecutively diagnosed patients with EM, to evaluate the PCR assay on clinical samples. Borrelia burgdorferi-specific DNA could be detected in urine specimens from the 12 patients with EM before antibiotic therapy. Five weeks after therapy all the patients were negative by PCR of urine. Results of the present study confirm that the described PCR assay is sensitive and that this sort of test allows monitoring of the efficacy of therapy in patients with early Lyme borreliosis.

Adult↗
PubMed1997

DNA typing of HLA-B27 by polymerase chain reaction.

To find a specific method for HLA-B27 typing, we tested an HLA-B27-specific polymerase chain reaction. This method was used for screening 100 randomly selected blood donors, 10 of them being HLA-B27 positive. A flow cytometric method and this PCR method were compared.

Flow Cytometry↗
PubMed1997

Frequencies of the CC chemokine receptor 5 delta 32 allele in various populations of defined racial background.

The 32-nucleotide deletion (delta 32) within the chemokine co-receptor CCR5 gene was studied in 1,031 DNA samples from various racial origins. The mutation is absent in 48 Vietnamese living in Paris, and we confirm that delta 32 allele is very rare in a sample of 302 individuals originating from sub-Saharan Africa. The mean delta 32 allelic frequency in unrelated non-HIV-1 infected blood donors is 0.113 in France, as calculated in a sample of 620 individuals. A slight decrease in allelic frequencies was noticed in the southern part of the country compared to the Paris region. In a population of 71 North African people the delta 32 frequency is 0.063, a value significantly lower than the mean frequency observed in France.

Africa South of the Sahara↗
PubMed1997

Pattern of gradient of apolipoprotein E allele *4 frequencies in western Europe.

The apolipoprotein E gene (APOE) is located on chromosome 19. The three most common APOE alleles account for most of the corresponding peptide chain variations in most human populations. APOE*3 is the most common allele, coding for the product E3; APOE*2 codes for an Arg-158-->Cys substitution (E2), and APOE*4 codes for a Cys-112-->Arg product (E4). We completed a meta-analysis of APOE allele frequencies from 30 geographically defined populations in Europe, including Iceland and Turkey. We performed a weighted multiple regression using normalized geographic coordinates and a fourth-degree polynomial. Next, we constructed maps showing isofrequencies of the *4 allele in Europe. We found a clear north to south decline in *4 allele frequency for continental Western Europe. No such clinal pattern was apparent for the *2 allele frequencies, but for *3 we found an inverse south to north decreasing gradient. Symmetry between the clines of the *4 and *3 alleles is due to a negative correlation coefficient (r = -0.89). We also plotted APOE allele frequencies against latitude; a decreasing cline was evident for *4 frequencies (y = -0.152 + 0.006x, r = 0.904) and an increasing cline was evident for *3 frequencies (y = 1.087 - 0.006x, r = 0.809). Clines for the APOE alleles could be the result of natural selection.

Alleles↗
PubMed1997

Identification of common cystic fibrosis mutations in African-Americans with cystic fibrosis increases the detection rate to 75%.

Cystic fibrosis (CF)--an autosomal recessive disorder caused by mutations in CF transmembrane conductance regulator (CFTR) and characterized by abnormal chloride conduction across epithelial membranes, leading to chronic lung and exocrine pancreatic disease--is less common in African-Americans than in Caucasians. No large-scale studies of mutation identification and screening in African-American CF patients have been reported, to date. In this study, the entire coding and flanking intronic sequence of the CFTR gene was analyzed by denaturing gradient-gel electrophoresis and sequencing in an index group of 82 African-American CF chromosomes to identify mutations. One novel mutation, 3120+1G-->A, occurred with a frequency of 12.3% and was also detected in a native African patient. To establish frequencies, an additional group of 66 African-American CF chromosomes were screened for mutations identified in two or more African-American patients. Screening for 16 "common Caucasian" mutations identified 52% of CF alleles in African-Americans, while screening for 8 "common African" mutations accounted for an additional 23%. The combined detection rate of 75% was comparable to the sensitivity of mutation analysis in Caucasian CF patients. These results indicate that African-Americans have their own set of "common" CF mutations that originate from the native African population. Inclusion of these "common" mutations substantially improves CF mutation detection rates in African-Americans.

Adolescent↗
PubMed1997

G542X as a probable Phoenician cystic fibrosis mutation.

When analyzed by origin, the frequency of the G542X cystic fibrosis (CF) mutation (the second most common CF mutation in Europe after DF508) varies between population groups in Europe. We show here that the frequency of G542X varies among different towns or regions of origin, being lower in northeastern Europeans than in southwestern Europeans. The G542X mutation mapping that we have defined by a multiple regression of G542X frequencies covers 28 countries (53 geographic points) and is based on data from 50 laboratories. The more elevated values of G542X frequency correspond to ancient sites of occupation by occidental Phoenicians.

Cystic Fibrosis↗
PubMed1997

High frequency of the apolipoprotein E *4 allele in African pygmies and most of the African populations in sub-Saharan Africa.

Apolipoprotein E genotypes (alleles *2, *3, and *4) have been determined in 70 Aka Pygmies and 470 unrelated African sub-Saharan subjects. Allele frequencies for Pygmies are 5.7% for APOE*2, 53.6% for APOE*3, and 40.7% for APOE*4, and the global proportions for sub-Saharan subjects are 11.6% for APOE*2, 70.6% for APOE*3, and 17.8% for APOE*4. The frequencies in some ethnic groups are statistically different from the overall mean in the Afar and the Isa, the Ewe (Togo), the Malinke (Guinea), and the Mossi; three ethnic groups have a higher allele frequency of APOE*4 (Fon, 29.4%; Zairians, 33.3%; Tutsi, 38.5%). The APOE*4 allele is considered the ancestral form because of its high frequency in African Pygmies and other aboriginal populations.

Africa South of the Sahara↗