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At least 271 records · Page 15Linked to original sources
PubMed2000

Phenotype-genotype correlations in a CMT2B family with refined 3q13-q22 locus.

OBJECTIVE: To perform genotype-phenotype correlation and genetic linkage analysis in a family with axonal Charcot-Marie-Tooth (CMT) syndrome and ulcero-mutilating features. BACKGROUND: CMT2B is a rare disorder belonging to the group of axonal CMT syndromes that is clinically characterized by marked distal muscle weakness and wasting as well as a high frequency of foot ulcers, infections, and amputations. So far only two families with this disorder have been described in which molecular genetic studies have shown evidence of autosomal dominant inheritance with linkage to chromosome 3q13-q22. METHODS: The authors report a large Austrian family presenting with the typical clinical features of CMT2B. Detailed clinical and electrophysiologic data were obtained in 15 at-risk individuals and DNA samples from 19 family members were collected for genetic linkage studies. RESULTS: Eight family members were definitely affected upon clinical and electrophysiologic examination and the majority revealed pronounced distal muscle wasting and weakness as well as prominent sensory abnormalities, which were frequently complicated by infections and amputations. Electrophysiologic studies showed normal or slightly to moderately slowed motor nerve conduction velocities, markedly reduced compound motor action potential amplitudes with chronodispersion, and absent or reduced amplitudes of sensory nerve action potentials. The molecular genetic study demonstrates linkage to chromosome 3q13-q22. Haplotype analysis in affected individuals indicates that the CMT2B locus is located between the flanking markers D3S1589 and D3S1549, representing a region of 10 cM. CONCLUSIONS: This family is the third CMT2B family reported so far and confirms the existence of the CMT2B locus on chromosome 3q13-q22, which is responsible for a clinically and electrophysiologically homogeneous disorder with prominent distal muscle weakness and wasting, and ulcero-mutilating features. Marked sensory disturbances and the high frequency of foot ulcers, infections, and amputations in our patients seem to be typical for CMT2B. Recombination events in affected individuals reduce the CMT2B candidate gene interval considerably from 25 to 10 cM.

Charcot-Marie-Tooth Disease↗
PubMed1998

Poststreptococcal reactive arthritis: clinical characteristics and association with HLA-DR alleles.

OBJECTIVE: To assess the relationship of poststreptococcal reactive arthritis (ReA) to other forms of ReA and rheumatic fever by comparing the frequency of HLA-B27 and DRB1 alleles in these diseases. METHODS: The diagnosis of poststreptococcal ReA was established in 25 children seen in a pediatric rheumatology clinic. HLA-B27 and DRB1 genotyping was performed in 18 of the white American patients. The DRB1 genotyping results were compared with those in 33 patients with rheumatic fever and 190 normal individuals. RESULTS: HLA-B27 was positive in 3 of the 18 poststreptococcal ReA patients, a frequency not different from that found in normal individuals. Compared with normal controls, the frequency of the DRB1*01 allele was higher in poststreptococcal ReA patients (odds ratio [OR] 2.7, P=0.044), while DRB1*16 was increased in patients with rheumatic fever (OR 4.3, P=0.028). CONCLUSION: The association of poststreptococcal ReA with HLA-DRB1*01, but not with HLA-B27, suggests that its pathogenesis may be more similar to that of rheumatic fever than to that of ReA associated with enteric pathogens.

Adolescent↗
PubMed2003

A novel screen for nuclear mitochondrial gene associations with Parkinson's disease.

Genetic factors play an important role in the aetiology of Parkinson's disease (PD). We have screened nuclear genes encoding subunits of mitochondrial complex I for associations between single nucleotide polymorphisms (SNPs) and PD. Abnormal functioning of complex I is well documented in human PD. Moreover, toxicological inhibition of complex I can lead to parkinsonism in animals. Thus, commonly occurring variants in these genes could potentially influence complex I function and the risk of developing PD. A sub-set of 70 potential SNPs in 31 nuclear complex I genes were selected and association analysis was performed on 306 PD patients plus 321 unaffected control subjects. Genotyping was performed using the DASH method. There was no evidence that the examined SNPs were significant genetic risk factors for PD, although this initial screen could not exclude the possibility that other disease-influencing variations exist within these genes.

Adult↗
PubMed2001

Hepatitis C virus genotypes and risk of cirrhosis in southern Italy.

Because hepatitis C virus (HCV) genotypes have raised considerable interest as variables that influence chronic hepatitis C progression, a case-control study was conducted to estimate their effects on patients with cirrhosis. Case patients (n = 46) had tested positive for anti-HCV antibody and HCV RNA and were residents of the study area who had cirrhosis recently diagnosed. Controls (n = 138) were drawn randomly from a residents' cohort from the same area. Demographic and other information were recorded. Presence of HCV infection, presence of HCV RNA, and HCV genotypes were assessed. Crude, stratified, and logistic regression analyses were performed. HCV genotype 2a/c occurred in 84 controls (60.9%) and 9 case patients (19.6%); HCV genotype 1b was found in 45 controls (32.6%) and 34 case patients (73.9%). HCV 1b genotype showed an independent effect on the risk of cirrhosis (odds ratio, 7.49; 95% confidence interval, 3.15--17.81). No significant effects related to other variables were observed. These results indicate that the genetic diversity of HCV phylogenetic variants may explain differences in biological behaviors.

Adult↗
PubMed2004

Monocyte chemoattractant protein-1 promoter -2518 polymorphism and schizophrenia in the Korean population.

The purpose of the present study was to investigate the association between the monocyte chemoattractant protein-1 (MCP-1) promoter -2518 polymorphism and schizophrenia. One hundred and twenty-three schizophrenic inpatients and 114 healthy controls participated in this study. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism. Genotype and allele distributions in patients with schizophrenia were not significantly different from those of the controls. However, distributions of genotypes and alleles were marginally different when considering subjects with positive and negative symptomatology. The present study therefore calls for further studies on the potential role of the MCP-1 promoter -2518 polymorphism in clinical heterogeneity of schizophrenia.

Base Sequence↗
PubMed2000

Glutathione S-transferase polymorphisms in MS: their relationship to disability.

BACKGROUND: Oxidative stress has been implicated in inflammatory demyelination. The glutathione S-transferase (GST) supergene family encodes isoenzymes that appear to be critical in protection against oxidative stress. Certain GST loci are polymorphic, demonstrating alleles that are null (GSTM1/GSTT1), encode low activity variants (GSTP1), or are associated with variable inducibility (GSTM3). OBJECTIVES: To investigate the association between clinical outcome in MS and allelic variants of GSTM1, GSTM3, GSTT1, and GSTP1. METHODS: Four hundred patients with clinically definite MS were studied. Disability was measured using the Kurtzke Expanded Disability Status Scale (EDSS). Disability was graded as mild (EDSS 0-4), moderate (4.5-5.5), or severe (EDSS 6-10). PCR-based genotyping was performed using DNA extracted from lymphocytes. Significant associations between GST genotypes and clinical outcome were corrected for gender, onset age, and disease duration using logistic regression. RESULTS: We found that the GSTM3 AA genotype was associated with severe disability in patients with a disease duration of more than 10 years (p = 0.027, n = 177, OR = 2.4, 95% CI = 1.1-5.0). Homozygosity for both GSTM1*0 and GSTP1*Ile105 containing allele was associated with severe disability in patients with a disease duration greater than 10 years (p = 0.022, n = 179, OR = 5.0, 95% CI = 1.3-19.8). CONCLUSIONS: Our results suggest that long-term prognosis in MS is influenced by a genetically determined ability to remove the toxic products of oxidative stress.

Adult↗
PubMed2005

No association of the 94T/G polymorphism in the adiponectin gene with diabetic complications.

AIM: This study examined a possible association of the T/G polymorphism at nucleotide 94 in the adiponectin gene with the prevalence of diabetic complications. METHODS: The study was performed in 696 patients with type 1 diabetes and type 2 diabetes. Genotyping was performed by means of polymerase chain reaction and subsequent cleavage by using SmaI restriction endonuclease. RESULTS: The 94G/G genotype was significantly more prevalent in patients with type 2 diabetes (2.2%) than in type 1 diabetics (0.0%) (p = 0.02), whereas no differences were found for frequencies of the 94T/T and the 94G/T genotypes, respectively. In patients with type 1 diabetes, 45 of 239 patients were heterozygous for the 94T/G polymorphism (carrier rate (CR): 18.8%; allele frequency (AF): 0.094). In type 2 diabetics, 71 of 457 patients were heterozygous and 10 patients were homozygous for the 94G/G genotype (CR: 17.7%; AF: 0.10). No association with diabetic nephropathy, diabetic neuropathy or diabetic retinopathy was found for either genotype in patients with type 1 and type 2 diabetes. CONCLUSIONS: The 94T/G polymorphism in the adiponectin gene is not associated with diabetic complications. The significance of a higher prevalence of the G allele in type 2, compared to type 1 diabetes remains to be clarified.

Adult↗
PubMed2005

Catechol-O-methyltransferase (COMT) genotypes and working memory: associations with differing cognitive operations.

BACKGROUND: Catechol-O-methyltransferase (COMT) is a strong candidate gene for schizophrenia and cognitive functions disrupted in this disorder. This report examines the relation of COMT genotypes to performance on a battery of working memory tests differing in the cognitive operations to be performed on the material. METHODS: A large sample of 402 healthy adults were tested on four working memory tests: Spatial Delayed Response (SDR), Word Serial Position Test (WSPT), N-back, and Letter-Number Sequencing. A subsample (n = 246) was tested on the Wisconsin Card Sorting Test (WCST). A saliva swab was used to obtain DNA from all participants. RESULTS: Letter-Number Sequencing, which requires both storage and manipulation of information, was the only working memory test that showed expected differences among COMT genotypes, with the met/met group showing the best performance and the val/val group the poorest performance. As in previous studies, the met/met group also performed better than the val/val group on the WCST. CONCLUSIONS: COMT genotypes were not associated with performance on tests measuring simple storage, maintenance of temporal order or updating of information in working memory. Genotype differences in Letter-Number Sequencing and WCST suggest that higher-order components of processing (e.g., mental manipulation) are more closely related to this gene.

Adolescent↗
PubMed2002

Host defense and inflammatory gene polymorphisms are associated with outcomes after HLA-identical sibling bone marrow transplantation.

We made the hypothesis that donor and recipient gene polymorphisms that drive the host response to microorganisms could be associated with infections after bone marrow transplantation (BMT). HLA-identical BMT was performed for patients with acute (n = 39) or chronic leukemia (n = 68). Genotyping was performed in 107 D/R DNA pairs for gene polymorphisms of cytokines (tumor necrosis factor-alpha [TNF-alpha] and TNF-beta, interleukin-1 receptor antagonist [IL-1Ra], IL-6, and IL-10), adhesion molecules (CD31 and CD54), Fcgammareceptors (FcgammaRIIa, IIIa, IIIb), mannose-binding lectin (MBL), and myeloperoxidase (MPO). First infection (overall) and first episodes of bacterial, viral, or invasive fungal infection were studied retrospectively for 180 days after BMT. Univariate and multivariate analyses, using death as a competing event, were performed to study risk factors. In multivariate analysis, first overall infections were increased in patients with the FcgammaRIIa R-131 genotype (hazard ratio [HR] = 1.92; P =.04), and severe bacterial infections were increased when the MPO donor genotype was AG or AA (HR = 2.16; P =.03). Viral and invasive fungal infections were not influenced by any genetic factor studied. Interestingly, we also found that (1) time to neutrophil recovery was shorter when donors were FcgammaRIIIb HNA-1a/HNA-1b (HR = 1.77; P =.002); (2) donor IL-1Ra (absence of IL-1RN*2) increased the risk for acute graft-versus-host disease (GVHD) (II-IV) (HR = 2.17; P =.017); and (3) recipient IL-10 (GG) and IL-1Ra genotypes increased the risk for chronic GVHD (P =.03 and P =.03, respectively). Finally, 180-day transplantation-related mortality rates were increased when donors were FcgammaRIIIb HNA-1a/HNA-1a or HNA-1b/HNA-1b (HR = 2.57; P =.05) and donor MPO genotype was AA (HR = 5.14; P =.004). In conclusion, donor and recipient gene polymorphisms are informative genetic risk factors for selecting donor/recipient pairs and could help in the understanding of mechanisms involved in host defenses of BM transplant recipients.

Adolescent↗
PubMed2005

Killer immunoglobulin-like receptor genotype in immune-mediated bone marrow failure syndromes.

OBJECTIVE: Recent reports have shown that killer immunoglobulin-like receptors (KIR) and KIR ligand (KIR-L) genotype play a role in the pathophysiology of autoimmune disorders. Certain KIR/KIR-L combinations might convey a predisposition to immune-mediated bone marrow failure. Examining the genotypic makeup of human leukocyte antigen (HLA) class I (KIR-L) and KIR in patients with hematologic disorders could offer clues to immunogenetic risk factors for these diseases. The objective of this study is to establish the frequency of specific KIR genes and KIR-L alleles in aplastic anemia (AA), paroxysmal nocturnal hemoglobinuria (PNH), myelodysplasia (MDS), and large granular lymphocyte leukemia (LGL), as compared with healthy control patients. METHODS: KIR genotyping was performed on DNA from 113 patients with AA, PNH, MDS, and LGL using sequence specific primer amplification. Results of genotypic KIR analysis were examined with HLA typing. Comparisons in frequency of KIR-L groups, KIR genotype profiles, and KIR/KIR-L mismatch were performed to determine whether specific KIR genes and KIR-L are overrepresented in bone marrow failure states. RESULTS: No difference in frequency of KIR-L groups was found relative to the healthy controls. AA and PNH showed decreased frequency of KIR-2DS1 and KIR-2DS5 genes: KIR-2DS1 35% vs 21% (p = 0.15) for AA and 19% for PNH (p = 0.13); KIR-2DS5 31% vs 14% (p = 0.08) for AA and 12% (p = 0.06) for PNH. These differences were even greater when compared to a larger group of control individuals from a study with similar genetic background. CONCLUSIONS: The reduced frequency of these KIR in AA and PNH may indicate an immunogenetic relationship between these diseases.

Anemia, Aplastic↗
PubMed2000

Differential performance among LDH-B genotypes in Rana lessonae tadpoles.

The European pool frog, Rana lessonae, is widely polymorphic for two common alleles (b,e) at the lactate dehydrogenase-B (LDH-B) locus. We compared fitness-related larval life-history traits among LDH-B genotypes, which originated from segregation in heterozygous parents, in an artificial pond experiment where tadpoles of R. lessonae from a Swiss population were raised together with tadpoles of the hemiclonal hybrid R. esculenta at two densities. In R. lessonae, LDH-B e/e homozygotes at each density had a higher proportion of metamorphs among survivors, reached metamorphosis earlier, and were heavier at metamorphosis than b/b homozygotes; b/e heterozygotes had intermediate values. That e/e individuals were superior to b/b in both time to and mass at metamorphosis is surprising because these two life-history traits are thought to reflect a performance trade-off; e/e genotypes apparently compensated for shorter time to metamorphosis by a higher growth rate. The two alleles showed the same performance ranking when combined in hybrids with a R. ridibunda allele: When R. esculenta from Swiss populations reared in the same ponds had received the e allele rather than the b allele from their R. lessonae parent, they reached metamorphosis earlier, but did not differ in mass at metamorphosis. The degree of linkage disequilibrium in the source population of the eight R. lessonae used as parents of the R. lessonae tadpoles is unknown, so we cannot exclude the possibility that the performance differences are caused by some anonymous tightly linked gene, rather than the LDH-B locus, that constitutes the genomically localized target of natural selection. A causal involvement of LDH-B is plausible, nevertheless, because this enzyme takes part in the central energy-metabolizing processes and has been reported to underlie fitness differences in other animals; also, differential performance of LDH-B genotypes has been observed in R. lessonae larvae from another population. The present results suggest strong directional selection for allele e; the sum of available data, including an independent laboratory experiment, suggests that partial environment-dependent overdominance combined with balancing selection favoring e/e homozygotes under some and b/b homozygotes under other conditions may be partially responsible for the broad maintenance of the LDH-B polymorphism in R. lessonae.

Alleles↗
PubMed1997

Genotypic mapping of HPV and assessment of EBV prevalence in endocervical lesions.

AIMS: To examine the prevalence of human papillomavirus (HPV) and Epstein-Barr virus (EBV) in low grade glandular intraepithelial lesions of the cervix, adenocarcinoma with high grade glandular intraepithelial lesions combined, and adenocarcinomas; and to perform a genotyping mapping analysis of endocervical carcinomas to determine the extent of HPV infections in such lesions. MATERIAL: Archival paraffin wax embeded material from the files of the departments of pathology, National Maternity Hospital, Dublin, and University College Cork, Ireland. METHODS: HPV prevalence was examined using type specific HPV PCR, general primer HPV PCR (pan HPV screen), nonisotopic in situ hybridisation (NISH), and PCR in situ hybridisation (PCR-ISH). In situ hybridisation was performed using fluorescein labelled oligonucleotide cocktail for eber transcripts of EBV. Genotypic analysis was performed, in all cases where possible, using a grid system. RESULTS: HPV 16 and 18 were predominantly identified in low grade glandular intraepithelial lesions, high grade glandular intraepithelial lesions, and adenocarcinomas, with HPV prevalence increasing with grade of dysplasia. EBV was only identified in subepithelial lymphocytes in a minority of cases. No link could be shown between HPV and EBV in endocervical lesions. HPV infection was not clonal in endocervical cancer and coexistent adjacent cervical intraepithelial neoplasia, where present, tended to show a similar HPV type. CONCLUSIONS: The restriction of HPV types 16 and 18 to endocervical lesions suggests that their effect is restricted and specific to endocervical mucosa, but the mechanism of interaction is currently unknown.

Adenocarcinoma↗
PubMed2003

Potential role of tetrahydrobiopterin in the treatment of maternal phenylketonuria.

OBJECTIVE: To evaluate the clinical relevance of tetrahydrobiopterin (BH4) supplementation for pregnant women with phenylketonuria (PKU)/hyperphenylalaninemia (HPA) and the possibility of treating these patients with BH4 instead of a phenylalanine (Phe)-restricted diet. METHODS: Genotyping was performed on 41 patients with PKU/HPA identified by newborn screening. Evaluating the genotype according to their BH4 responsiveness is published. Follow-up of 3 patients with mild PKU treated with BH4 is evaluated. Discussion of the transfer of these experiences to the possibility of treating mothers at risk for maternal PKU is presented. RESULTS: In 41 patients with PKU/HPA, we found 17 (41%) bearing at least 1 allele with a mutation described as being responsive to BH4. In 8 of the patients, BH4 loading had been performed in the newborn period, in 6 of whom the test showed a clear decrease of blood Phe 4 and 8 hours after loading. One of the nonresponders was reinvestigated at 3 years of age, showing a clear response (genotype Y414C/R408W): BH4 supplementation resulted in a much higher Phe tolerance (500 instead of 250 mg/day) with blood Phe levels <200 micromol/L. Two children (genotype E390G/IVS10-11g>a and L48S/L48S, respectively) were treated with BH4 only (15-20 mg/kg body weight/day), one from birth, the other from 2 years of age. Blood Phe decreased from >800 micromol/L to a mean of 321.4 and 331.7 micromol/L, respectively (range: 141-718 micromol/L) under a normal diet (total observation time: 4 years). Development was normal with no adverse reactions. CONCLUSIONS: BH4 supplementation seems to be a promising alternative treatment in some patients with mild PKU. Because blood Phe levels in maternal PKU should be maintained at 120 to 360 micromol/L, clinical relevance may be even greater than for treatment of children with PKU/HPA. BH4 supplementation may also be combined with a Phe-restricted diet, allowing higher Phe intake and protecting mothers from high Phe blood peaks. However, additional studies are necessary to prove the safety and economy of such an alternative treatment in patients with PKU/HPA, especially during pregnancy.

Biopterins↗
PubMedDate not supplied

Cystic fibrosis screening using the College panel: platform comparison and lessons learned from the first 20,000 samples.

PURPOSE: To determine the accuracy of two commercially available kits for cystic fibrosis (CF) genotyping and determine allele frequencies for the ACMG/ACOG recommended mutations. METHODS: A total of 1,040 consecutive analyses using Roche CF Gold Strips and the ABI CF Genotyper were performed. Subsequently we performed analyses of 20,103 samples. RESULTS: Both kits accurately determined CF genotypes. The I148T mutation was found >100 times more frequently in carrier screening than in CF patients. Asymptomatic patients were identified who are compound heterozygotes for delta F508 and I148T. Four of 13 patients heterozygous for delta F508 and the IVS8-5T polymorphism had some symptoms of CF. CONCLUSION: Accurate and timely analysis can be performed for the ACMG CF panel. I148T is a low penetrance CF allele.

Alleles↗
PubMed2002

Human leukocyte antigen alleles in patients with bipolar disorder in the Korean population.

We performed an association study between human leukocyte antigen (HLA) alleles and bipolar disorder to evaluate the potentiality of HLA as a genetic marker in bipolar disorder. HLA class I and class II allele frequencies were assessed in 87 bipolar patients and were compared with those of 206 normal controls in the Korean population. HLA class I typing was performed using the microlymphocytotoxicity method, whereas class II (DRB1 and DQB1) genotyping was performed with polymerase chain reaction-sequence specific oligonucleotide probes. When the allele frequency of HLA in bipolar patients was compared with that in normal controls, there were some significant differences. Bipolar patients showed statistically significant increased allele frequencies of HLA-A29 and B54. Allele frequencies of HLA-B51 and DRB1*02 were significantly higher in normal controls. However, these results were no longer significant after correcting for the number of alleles. The results of the present study suggest that HLA alleles may not confer susceptibility to bipolar disorder in the Korean population. To clarify the genetic influence of HLA on bipolar disorder, we should conduct a consecutive study with a larger cohort of subjects.

Adolescent↗
PubMed2002

Genetic dissection of an elite rice hybrid revealed that heterozygotes are not always advantageous for performance.

We introduced an experimental design that produced an "immortalized F(2)" population allowing for complete dissection of genetic components underlying quantitative traits. Data for yield and three component traits of the immortalized F(2) were collected from replicated field trials over 2 years. Using 231 marker loci, we resolved the genetic effects into individual components and assessed relative performance of all the genotypes at both single- and two-locus levels. Single-locus analysis detected 40 QTL for the four traits. Dominance effects for about one-half of the QTL were negative, resulting in little "net" positive dominance effect. Correlation between genotype heterozygosity and trait performance was low. Large numbers of digenic interactions, including AA, AD, and DD, were detected for all the traits, with AA as the most prevalent interaction. Complementary two-locus homozygotes frequently performed the best among the nine genotypes of many two-locus combinations. While cumulative small advantages over two-locus combinations may partly explain the genetic basis of heterosis of the hybrid as double heterozygotes frequently demonstrated marginal advantages, double heterozygotes were never the best genotypes in any of the two-locus combinations. It was concluded that heterozygotes were not necessarily advantageous for trait performance even among genotypes derived from such a highly heterotic hybrid.

Epistasis, Genetic↗
PubMed2000

Antigenic and genetic characterization of the fusion (F) protein of mumps virus strains.

Twelve strains of mumps virus, belonging to the A, C and D genotypes of the small hydrophobic (SH) protein gene, were investigated by nucleotide sequencing of the fusion protein gene. The nucleotide sequences and deduced amino acid sequences were aligned and compared with previously reported sequences of the gene. In addition an antigenic comparison between the F protein of different strains of the A, C and D genotypes was performed with ten monoclonal antibodies directed against the F protein of genotype A. Phylogenetic analysis of the coding region of the F gene showed the expected clustering of the different genotypes, as previously determined from the SH protein gene. Comparison of the 538 long amino acid sequence of the protein showed that only a small number of amino acids differed between the viral strains. The A genotype differed from B, C and D whereas the latter showed fewer consistent amino acid differences between themselves. Nine of the ten monoclonal antibodies reacted with the C and D genotypes and one failed to react with these genotypes. It is concluded that the structure and antigenicity of the F protein is well conserved both intra- and intergenotypically over long periods of time.

Amino Acid Sequence↗
PubMed2006

Polymorphisms and resistance mutations in the protease and reverse transcriptase genes of HIV-1 F subtype Romanian strains.

OBJECTIVE: To evaluate the prevalence of resistance mutations in the genome of HIV-1 F subtype strains isolated from Romanian antiretroviral (ARV) treatment-naïve patients and to assess the phylogenetic relatedness of these strains with other HIV-1 strains. METHODS: Twenty-nine HIV-1 strains isolated from treatment-naïve adolescents (n=15) and adults (n=14) were included in this study. Resistance genotyping was performed by using Big Dye Terminator chemistry provided by the ViroSeq Genotyping System. The sequences of the protease and reverse transcriptase genes were aligned (ClustalW) and a phylogenetic tree was built (MEGA 3 software). For subtyping purposes, all the nucleotide sequences were submitted to the Stanford database. RESULTS: All the studied strains were found to harbor accessory mutations in the protease gene. The most frequent mutation was M36I (29 of 29 strains), followed by L63T, K20R, and L10V. The number of polymorphisms associated with protease inhibitor resistance was different for the two age groups. Intraphylogenetic divergence was greater for adults than for adolescents infected in childhood. All the strains were found to belong to the F1 subtype. The phylogenetic analysis revealed that Romanian strains clustered together, but distinctly from F1 HIV-1 strains isolated in other parts of the world (Brazil, Finland, and Belgium). CONCLUSION: Protease secondary mutations are present with high frequency in the HIV-1 F subtype strains isolated from Romanian ARV treatment-naïve patients, but no major resistance mutations were found.

Adolescent↗