PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Phenotype modifier”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 757 records · Page 42Linked to original sources

Patterns of dyslipoproteinemia in selected North American populations. The Lipid Research Clinics Program Prevalence Study.

This article describes the assignment of dyslipoproteinemia (DLP) in several free-living North American populations and presents mean lipid and lipoprotein levels for each type. Dyslipoproteinemic phenotypes were assigned by a modified version of the National Institutes of Health (Fredrickson) phenotyping system. Criteria for assigning phenotypes included age- and sex-specific 5th and 95th percentiles for low-density lipoprotein and high-density lipoprotein cholesterol and total triglyceride, as well as other qualitative and quantitative criteria. Phenotypes IIb, III, I, and V were uncommon, confirming clinical impressions of their frequency. Lipid and lipoprotein levels in specific phenotypes were generally as expected. In the type III phenotype, however, mean cholesterol and triglyceride levels were surprisingly low. Gonadal hormone use, in the form of both oral contraceptives and postmenopausal estrogens, was reported in approximately 30% of women in these populations and was associated with dramatic differences in the frequency of DLP when compared with women not taking hormones. In general, these differences reflected the previously described effects of estrogen and progestins on lipoprotein levels. These data gathered in free-living populations: confirm clinical impressions of the rarity of some phenotypes, focus attention on those phenotypes in which diminished rather than elevated lipoproteins are found, and provide further evidence of the effect of hormones on lipid and lipoprotein levels.

Adolescent↗

[Gaucher disease: clinical, genetic and therapeutic aspects].

Gaucher disease (GD) is one of the most prevalent lysosomal storage disorders and one of the rare genetic diseases for which therapy is now available. Partial deficiency of glucocerebrosidase is associated with parenchymal disease of the liver, spleen, and bone marrow with concomitant anaemia and thrombocytopenia in non-neuronopathic, type 1, Gaucher disease. Severe deficiency of glucocerebrosidase caused by disabling mutation is additionally associated with neurological manifestations in the less common type 2 and type 3 Gaucher diseases. Outside of the Ashkenazi Jewish community, a high molecular diversity is observed. Clarification of genotype-phenotype relationship and the identification of modifier loci that impact on Gaucher disease phenotypes remain a critical area for research. Recombinant glucocerebrosidase (imiglucerase) is an effective mean of treating type 1 Gaucher disease and should be initiated early on in life. Amelioration of hepatosplenomegaly and of haematological manifestations is usually apparent within six months. Bone disease responds more slowly. Imiglucerase has recently been approved for the treatment of type 3 Gaucher disease. Enzyme replacement therapy cannot reverse the neurological deficits in type 2 or type 3 Gaucher disease. This should prompt further research on substrate deprivation and gene therapy.

Gaucher Disease↗

New Methods for Extraction and Quantitation of Zeins Reveal a High Content of gamma-Zein in Modified opaque-2 Maize.

We have developed methods for quantitative extraction and analysis of zeins from maize (Zea mays L.) flour. Extraction involved solubilization of total endosperm proteins in an alkaline buffer containing SDS and 2-mercaptoethanol with subsequent precipitation of nonzein proteins by the addition of ethanol to 70%. Analysis of these proteins by SDS-PAGE with Coomassie blue staining and by Western blotting and ELISA assay with zein antibodies revealed that this extraction method is more quantitative than the traditional Landry-Moureaux procedure, especially for the beta- and gamma-zeins. This method was used to extract and analyze the zein content of several ;Quality Protein Maize' (QPM) varieties developed by the International Maize and Wheat Improvement Center. QPM varieties contain ;modifier genes' that confer a vitreous phenotype on opaque-2 genotypes, while maintaining the elevated levels of lysine and tryptophan characteristic of this mutant. This analysis revealed that the QPM types contain 2 to 4 times the amount of the gamma-zein than unmodified opaque-2 or normal maize varieties. Possible relationships between the high expression of the gamma-zein and the modified opaque phenotype are discussed.

Journal Article↗

Extremely low penetrance of hearing loss in four Chinese families with the mitochondrial 12S rRNA A1555G mutation.

Mutations in mitochondrial DNA (mtDNA) have been found to be associated with sensorineural hearing loss. We report here the clinical, genetic, and molecular characterization of four Chinese pedigrees with aminoglycoside-induced and nonsyndromic hearing impairment. Clinical evaluation revealed the variable phenotype of hearing impairment including audiometric configuration in these subjects, although these subjects share some common features: bilateral and sensorineural hearing impairment. Strikingly, these Chinese pedigrees exhibited extremely low penetrance of hearing loss (5.2%, 4.8%, 4.2%, and 13.3%, respectively, and with an average 8% penetrance). In particular, four of all five affected matrilineal relatives of these pedigrees had aminoglycoside-induced hearing loss. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the distinct sets of mtDNA polymorphism, in addition to the identical homoplasmic A1555G mutation, associated with hearing impairment in many families from different genetic backgrounds. The fact that mtDNA of those pedigrees belonged to different haplogroups R9a, N9a, D4a, and D4 suggested that the A1555G mutation occurred sporadically and multiplied through evolution of the mtDNA in China. However, there was the absence of functionally significant mutations in tRNA and rRNAs or secondary LHON mutations in these Chinese families. These data imply that the nuclear background or/and mitochondrial haplotype may not play a significant role in the phenotypic expression of the A1555G mutation in these Chinese pedigrees. However, aminoglycoside appears to be a major modifier factor for the phenotypic manifestation of the A1555G mutation in these Chinese families.

Adult↗

Heritability of MRI lesion volume in CADASIL: evidence for genetic modifiers.

BACKGROUND AND PURPOSE: The phenotypic expressivity shows striking variability among individuals with CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy), a small vessel disease caused by mutations in NOTCH3. However, little is known about the factors that underlie this variability. We sought to quantify the contribution of modifying genetic effects to individual differences in the volume of cerebral ischemic lesions. METHODS: One hundred and fifty-one affected individuals (mean age+/-SD=45.7+/-10.4) from 95 unrelated families with CADASIL underwent MRI. The volume of lesions visible on T2-weighted images and the intracranial volume (ICV) were quantified and vascular risk factors were assessed. Because of a skewed distribution, lesion volume measures were square-root transformed. Variance component methods were used to estimate the heritability of lesion volumes (ie, the proportion of variation caused by additive genetic factors) after adjusting for covariates. RESULTS: In multivariate analyses, higher age, a larger ICV, and a higher diastolic blood pressure were independently associated with a larger volume of T2-visible lesions (all P<0.05). After adjustment for age the point estimate for the heritability of the square-root-transformed measure of T2 lesion volume was 0.634 (SE=+/-0.286). Adjustment for age, sex, ICV, and diastolic blood pressure increased the estimated heritability to 0.738 (SE+/-0.255). CONCLUSIONS: Heritability estimates in CADASIL suggest a strong modifying influence of genetic factors distinct from the causative NOTCH3 mutation on the amount of ischemic brain lesions. These findings justify a systematic search for genetic variants that modify disease progression.

Adult↗

Antitumor effects of interleukin-2 gene-modified fibroblasts in an orthotopic colon cancer model.

We transduced the interleukin-2 (IL-2) gene into murine fibroblasts BALBCL7 or murine colon cancer CT26 using a retroviral vector. BALBCL7 transduced with IL-2 gene secreted 748 pg/ml of IL-2, whereas IL-2 gene-modified CT26 secreted 1,167 pg/ml of IL-2 (48 h incubation, 1x10(6)/ml). Then, we inoculated gene-modified BALBCL7 and/or CT26 cells into BALB/c female mice, and observed the tumor growth. The tumor growth was inhibited in mice inoculated with parental CT26 plus IL-2 gene-modified BALBCL7, compared with that in mice given parental CT26 alone (P<0.01). Moreover, we investigated the cytotoxic activity of spleen cells derived from mice treated with gene-modified cells, and performed phenotypic analysis of the effector cells. The killer cells derived from mice inoculated with IL-2 gene-modified BALBCL7 plus parental CT26 showed higher cytotoxic activity than those from mice inoculated with CT26 alone. The cytotoxic activity was almost completely blocked by anti-CD8 antibody (Ab), and partially blocked by anti-asialo GM1 Ab. Next, we inoculated CT26 tumor tissue into murine cecum orthotopically, and treated the animals with gene-modified BALBCL7 plus parental CT26. The tumor size in the cecum was significantly decreased, compared with parental CT26 alone (P<0.01).

Animals↗

Adaptation to spatially heterogeneous modifying and adaptive environments.

The development of an individual's phenotype is influenced by environmental factors (the modifying environment) which may differ from those factors (the adaptive environment) that decide on the adaptational value of the developed phenotype. The shapes of adaptationally optimal norms of reaction are therefore essentially determined by associations between these two environmental components together with the degree of adaptational sensitivity of the developed phenotypes. Two complementary aspects of optimality are accounted for: (a) environments can be optimal for a given norm of reaction and (b) norms of reaction can be optimal for a given environment. The results are obtained for random distribution of genotypes over environmental conditions and under the physiologically reasonable premise that fitness is a function of the costs of modification and adaptation. It turned out that the associations of adaptive and modifying environments are the primary sources of adaptational optimization. More specifically, it is shown that (i) independence between the two environmental components constitutes an adaptationally optimal environment only for norms of reaction in which all phenotypes are adaptively insensitive; (ii) if costs of modification do not depend on the environment, and if the two environmental components are not associated, adaptationally optimal norms of reaction can always be realized through phenogenetic invariance; (iii) as a rule, adaptively sensitive phenotypes developed under strong environmental associations necessitate phenogenetic plasticity for the optimal norm of reaction; (iv) a norm of reaction which is adaptationally optimal in its adaptationally optimal environment can always be realized through phenogenetic invariance, if costs of modification do not vary with the environment. These results reveal an important role of patterns of adaptive sensitivity of phenotypes, which may even surpass that of shapes of norms of reaction in adaptational processes.

Adaptation, Physiological↗

Clinical evaluation and mitochondrial DNA sequence analysis in two Chinese families with aminoglycoside-induced and non-syndromic hearing loss.

We report here the clinical, genetic, and molecular characterization of two Chinese pedigrees with aminoglycoside-induced and non-syndromic hearing impairment. Clinical evaluation revealed the variable phenotype of hearing impairment including audiometric configuration in these subjects. Penetrances of hearing loss in BJ105 and BJ106 pedigrees are 67% and 33%, respectively. In particular, three of 10 affected matrilineal relatives of BJ105 pedigree had aminoglycoside-induced hearing loss, while seven affected matrilineal relatives in BJ105 pedigree and six affected matrilineal relatives in BJ106 pedigree did not have a history of exposure to aminoglycosides. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the identical homoplasmic A1555G mutation and distinct sets of mtDNA variants belonging to haplogroups F3 and M7b. These variants showed no evolutionary conservation, implying that mitochondrial haplotype may not play a significant role in the phenotypic expression of the A1555G mutation in these Chinese pedigrees. However, aminoglycosides and nuclear backgrounds appear to be major modifier factors for the phenotypic manifestation of the A1555G mutation in these Chinese families.

Aminoglycosides↗

Stability of debrisoquine (CYP2D6) phenotype in liver transplant patients.

Liver metabolism may be modified after liver transplantation according to the phenotype of the donor and may be influenced by posttransplantation complications. The CYP2D6 phenotype was assessed in 13 patients (group I) before and after liver transplantation using debrisoquine. CYP2D6 activity was also assessed in vitro on microsomes from the liver of the recipients and the donors, using dextromethorphan. Twelve patients were extensive metabolizers both before and after transplantation. One apparently poor metabolizer was transplanted with the liver of another poor metabolizer. The intrinsic clearance of dextromethorphan (CL(int)) measured on recipient liver microsomes was significantly lower than that on donor liver microsomes (p < 0.05). In extensive metabolizers, the debrisoquine metabolic ratio was correlated with CL(int) before (r = 0.78, p < 0.05) and after (r = 0.89, p < 0.0005) transplantation. Debrisoquine phenotype was measured repeatedly in nine additional patients (group II) up to 3 years after liver transplantation. Their phenotype was stable during the follow-up observation, although the variations observed may be clinically relevant. Therefore, no change in CYP2D6 phenotype (extensive/poor metabolizer) was observed because of the liver transplantation, and the debrisoquine log metabolic ratio was largely unaffected by the liver complications observed during the posttransplantation follow-up observation.

Cytochrome P-450 CYP2D6↗

Expression of biologically active hordothionins in tobacco. Effects of pre- and pro-sequences at the amino and carboxyl termini of the hordothionin precursor on mature protein expression and sorting.

Hordothionins (HTHs) are small anti-bacterial proteins present in barley endosperm which are processed from larger precursor proteins, consisting of an amino-terminal signal peptide (SP), the mature highly basic HTH and a carboxy-terminal acidic peptide (AP). Different HTH precursor proteins were expressed in tobacco to study the effects of the pre-sequences (SP) and pro-sequences (AP) on expression, processing, sorting and biological activity and hence the feasibility of engineering bacterial disease resistance into crops which lack these proteins. Maximum HTH expression levels of approximately 0.7% (11 mumol/kg) of total soluble protein in young tobacco leaves were obtained using a semi-synthetic gene construct encoding a complete chimaeric HTH precursor protein. Tenfold lower HTH expression levels (maximum 1.3 mumol/kg) were obtained using synthetic gene constructs without the AP-coding sequence and no expression was found in plants containing synthetic HTH gene constructs without SP- and AP-coding sequences. In both cases where expression was found, the precursors were apparently correctly processed, although the HTH produced in plants containing a construct without AP sequence appeared to be slightly modified. No effect on plant phenotype was observed. Localization studies indicated that the HTH was in identical fractions of plants expressing the two different precursors, albeit at a different ratio, and was not secreted into the intercellular spaces of leaves or culture medium by protoplasts. Our results indicated that the AP is not involved in sorting and suggested that it might facilitate transport through membranes. The in vitro toxicity of HTH isolated from transgenic tobacco plants expressing the two different precursor proteins for the bacterial plant pathogen Clavibacter michiganensis subsp. michiganensis appeared similar to that of the HTH purified from barley endosperm.

Amino Acid Sequence↗

Imaging genomics and response to treatment with antipsychotics in schizophrenia.

Recent important advancements in genomic research have opened the way to new strategies for public health management. One of these questions pertains to how individual genetic variation may be associated with individual variability in response to drug treatment. The field of pharmacogenetics may have a profound impact on treatment of complex psychiatric disorders like schizophrenia. However, pharmacogenetic studies in schizophrenia have produced conflicting results. The first studies examined potential associations between clinical response and drug receptor genes. Subsequent studies have tried to use more objective phenotypes still in association with drug receptor genes. More recently, other studies have sought the association between putative causative or modifier genes and intermediate phenotypes. Thus, conflicting results may be at least in part explained by variability and choice of the phenotype, by choice of candidate genes, or by the relatively little knowledge about the neurobiology of this disorder. We propose that choosing intermediate phenotypes that allow in vivo measurement of specific neuronal functions may be of great help in reducing several of the potential confounds intrinsic to clinical measurements. Functional neuroimaging is ideally suited to address several of these potential confounds, and it may represent a powerful strategy to investigate the relationship between behavior, brain function, genes, and individual variability in the response to treatment with antipsychotic drugs in schizophrenia. Preliminary evidence with potential susceptilibity genes such as COMT, DISC1, and GRM3 support these assumptions.

Antipsychotic Agents↗

Mutations in MTO2 related to tRNA modification impair mitochondrial gene expression and protein synthesis in the presence of a paromomycin resistance mutation in mitochondrial 15 S rRNA.

Nuclear gene(s) have been shown to modulate the phenotypic expression of mitochondrial DNA mutations. We report here the identification and characterization of the yeast nuclear gene MTO2 encoding an evolutionarily conserved protein involved in mitochondrial tRNA modification. Interestingly, mto2 null mutants expressed a respiratory-deficient phenotype when coexisting with the C1409G mutation of mitochondrial 15 S rRNA at the very conservative site for human deafness-associated 12 S rRNA A1491G and C1409T mutations. Furthermore, the overall rate of mitochondrial translation was markedly reduced in a yeast mto2 strain in the wild type mitochondrial background, whereas mitochondrial protein synthesis was almost abolished in a yeast mto2 strain carrying the C1409G allele. The other interesting feature of mto2 mutants is the defective expression of mitochondrial genes, especially CYTB and COX1, but only when coexisting with the C1409G allele. These data strongly indicate that a product of MTO2 functionally interacts with the decoding region of 15 S rRNA, particularly at the site of the C1409G or A1491G mutation. In addition, we showed that yeast and human Mto2p localize in mitochondria. The isolated human MTO2 cDNA can partially restore the respiratory-deficient phenotype of yeast mto2 cells carrying the C1409G mutation. These functional conservations imply that human MTO2 may act as a modifier gene, modulating the phenotypic expression of the deafness-associated A1491G or C1409T mutation in mitochondrial 12 S rRNA.

Alleles↗

Determinants of bleeding severity in von Willebrand disease.

von Willebrand disease (VWD) is one of the most common bleeding disorders. It is caused by abnormalities in the von Willebrand factor (VWF) protein, and is characterized by incomplete penetrance and variable expressivity. VWF levels vary widely in the population. The best-characterized human genetic modifier of VWF is the ABO blood group. Patients with VWD show considerable variation in bleeding tendency even within the same family, independently of VWF levels. It is possible that several modifier genes influence the phenotype. Variants of genes that encode for platelet receptors as well as those that encode for clotting factor levels have been proposed as modifiers. It is hoped that new clinical-genetic studies will shed light on these issues and help practitioners to determine the population at risk for bleeding.

Animals↗

Modifier genes and heart failure.

Recent progress in genomic applications have led to a better understanding of the relationship between genetic background and cardiovascular diseases such as heart failure. A considerable component of the variability in heart failure outcome is due to modifier genes, i.e. genes that are not involve in the genesis of a disease but modify the severity of the phenotypic expression once the disease has developed. The strategy most commonly used to identify modifier genes is based on association studies between the severity of the phenotype of the disease (morbidity and/or mortality) and the sequence variation(s) of selected candidate gene(s). This strategy has showed that several polymorphisms of the beta1 and beta2 adrenergic receptors genes and the angiotensin converting enzyme gene are correlated to the prognosis of patients with heart failure. Recently, we have applied an experimental strategy, known as genome mapping, for the identification of heart failure modifier genes. Genome mapping has previously been used with success to identify the genes involved in the development of both monogenic and multifactorial diseases. We have showed that the prognosis of heart failure mice, induced through overexpressing calsequestrin, is linked to 2 Quantitative Trait Loci (QTL) localized on chromosome 2 and 3. Using both strategies (candidate gene and genome mapping) should allow us to identify a number of modifier genes that may provide a more rational approach to identify patients at risk for disease and response to therapy.

Calsequestrin↗

Complex genomic rearrangement of ALK loci associated with integrated human Epstein-Barr virus in a post-transplant myogenic liver tumor.

Epstein-Barr virus (EBV) is a ubiquitous viral agent, well known to be associated with lymphoid, epithelial, and smooth-muscle malignancies in immunocompromised individuals. This report describes a 10-year-old patient with an EBV-related liver tumor occurring after kidney transplantation. The neoplasm presented a phenotypic spectrum, ranging from a smooth-muscle tumor to an inflammatory pseudotumor (IPT). The neoplastic cells failed to disclose CD21, CD35, or ALK expression, the latter confirmed by reverse-transcription polymerase chain reaction. Cytogenetic analysis revealed a single clonal cell population showing 46,XY,del (2)(p23),der(3)t (2;3)(p23;q29),der(21) t(Y;21)(q12;p13) karyotype. By metaphase FISH analysis, the neoplastic cells demonstrated the presence of two molecularly different but related aberrant clones, one with the loss of one ALK allele and the second with translocation of the 3'end of ALK kinase domain on the der(3) chromosome. Using FISH with an EBV-specific and 3'end ALK DNA probes, a co-localization of the viral DNA and the ALK sequences was found on the der(3) chromosome. Metaphases with loss of rearranged ALK did not show integrated virus; instead, viral particles together with an associated 3'end ALK domain formed an ex-chromosomal, episomal-like type configuration. The interphase study, using dual-color 5'/3' end ALK FISH assay, revealed 30% of nuclei with only one fused signal, confirming the total loss of one ALK allele in the subset of tumor cells. A combined immunofluorescence and FISH study indicated this separate clonal variant to correspond to desmin-positive smooth-muscle cells. In contrast, desmin-negative myofibroblasts showed the presence of both normal and rearranged ALK alleles. Our results indicate that ALK locus may be a target of EBV integration, a hitherto unreported finding. Although the sustained clonal expansion in EBV-related smooth-muscle tumors/IPTs may depend on functions provided by the EBV oncogenic proteins, the tumor phenotype may be further modified by the secondary genomic rearrangements imposed by the virus during and/or after the integration event. In this respect, the observed phenotypic heterogeneity most likely reflects divergence during neoplastic progression, with the subsequent expansion of morphologically and molecularly distinct but cytogenetically related clones.

Anaplastic Lymphoma Kinase↗

Impact of genetic polymorphisms on heart failure prognosis.

Recent progress in genomic applications have led to a better understanding of the relationship between genetic background and cardiovascular diseases such as heart failure. The broad variability in heart failure patient outcome is in part secondary to modifier genes, i.e. genes that are not involved in the genesis of a disease but modify the severity of the phenotypic expression once the disease has developed. The strategy most commonly used to identify modifier genes is based on association studies between the severity of the phenotype and the sequence variation(s) of selected candidate gene(s). Using this strategy, several polymorphisms of the beta 1 and beta 2-adrenergic receptors genes and the angiotensin converting enzyme gene have been correlated to the prognosis of patients with heart failure. Recently, we have applied an experimental strategy, known as genome mapping, for the identification of heart failure modifier genes. Genome mapping has previously been used with success to identify the genes involved in the development of both monogenic and multifactorial diseases. We have shown that the prognosis of heart failure mice, induced through calsequestrin overexpression, is linked to two Quantitative Trait Loci localized on chromosomes 2 and 3. Using both strategies (candidate gene and genome mapping) should allow us to identify a number of modifier genes that may provide a more rational approach to identify patients with the worst prognosis and to predict their response to therapy.

AMP Deaminase↗

The role of heterozygosity for CYP21 in the polycystic ovary syndrome.

The phenotypic heterogeneity recognized in congenital adrenal hyperplasia secondary to 21-hydroxylase deficiency appears to extend to 21hydroxylase (CYP21) mutation carriers. To begin the search for modifying loci responsible for this phenotypic heterogeneity, we performed CYP21 genotype analysis and assays for three candidate modifier loci on genomic DNA samples obtained from 30 adolescent girls with hyperandrogenism, 14 healthy control women, and 15 female obligate CYP21 mutation carriers. The frequency of heterozygosity for CYP21 mutations was increased in women with symptomatic hyperandrogenism (10/30) compared to healthy controls (1/14). There were no significant differences in the frequencies of the modifier variants among the three groups. Although the small sample size precludes strong conclusions, CYP21 nonsense mutation carriers tend to be asymptomatic while missense mutation carriers, i.e. V281L, appear to manifest a PCOS phenotype. Evaluation of additional modifying loci in larger series of patients will help identify new genetic markers associated with PCOS.

Adolescent↗

Respiratory epithelial gene expression in patients with mild and severe cystic fibrosis lung disease.

Despite having identical cystic fibrosis transmembrane conductance regulator genotypes, individuals with DeltaF508 homozygous cystic fibrosis (CF) demonstrate significant variability in severity of pulmonary disease. This investigation used high-density oligonucleotide microarray analysis of nasal respiratory epithelium to investigate the molecular basis of phenotypic differences in CF by (1) identifying differences in gene expression between DeltaF508 homozygotes in the most severe 20th percentile of lung disease by forced expiratory volume in 1 s and those in the most mild 20th percentile of lung disease and (2) identifying differences in gene expression between DeltaF508 homozygotes and age-matched non-CF control subjects. Microarray results from 23 participants (12 CF, 11 non-CF) met the strict quality control guidelines and were used for final data analysis. A total of 652 of the 11,867 genes identified as present in 75% of the samples were significantly differentially expressed in one of the three disease phenotypes: 30 in non-CF, 53 in mild CF, and 569 in severe CF. An analysis of genes differentially expressed by severity of CF lung disease demonstrated significant upregulation in severe CF of genes involved in protein ubiquination (P < 0.04), mitochondrial oxidoreductase activity (P < 0.01), and lipid metabolism (P < 0.03). Analysis of genes with decreased expression in patients with CF compared with control subjects demonstrated significant downregulation of genes involved in airway defense (P < 0.047) and protein metabolism (P < 0.048). This study suggests that differences in CF lung phenotype are associated with differences in expression of genes involving airway defense, protein ubiquination, and mitochondrial oxidoreductase activity and identifies specific new candidate modifiers of the CF phenotype.

Adolescent↗