The incremental yield of prenatal exome sequencing over chromosome microarray for congenital heart abnormalities: A systematic review and meta-analysis

OBJECTIVES

To determine the incremental yield of prenatal exome sequencing (PES) over standard testing in fetuses with an isolated congenital heart abnormality (CHA), CHA associated with extra-cardiac malformations (ECMs) and CHA dependent upon anatomical subclassification.

METHODS

A systematic review of the literature was performed using MEDLINE, EMBASE, Web of Science and grey literature January 2010-February 2023. Studies were selected if they included greater than 20 cases of prenatally diagnosed CHA when standard testing (QF-PCR/chromosome microarray/karyotype) was negative. Pooled incremental yield was determined. PROSPERO CRD 42022364747.

RESULTS

Overall, 21 studies, incorporating 1957 cases were included. The incremental yield of PES (causative pathogenic and likely pathogenic variants) over standard testing was 17.4% (95% CI, 13.5%-21.6%), 9.3% (95% CI, 6.6%-12.3%) and 35.9% (95% CI, 21.0%-52.3%) for all CHAs, isolated CHAs and CHAs associated with ECMs. The subgroup with the greatest yield was complex lesions/heterotaxy; 35.2% (95% CI 9.7%-65.3%). The most common syndrome was Kabuki syndrome (31/256, 12.1%) and most pathogenic variants occurred de novo and in autosomal dominant (monoallelic) disease causing genes (114/224, 50.9%).

CONCLUSION

The likelihood of a monogenic aetiology in fetuses with multi-system CHAs is high. Clinicians must consider the clinical utility of offering PES in selected isolated cardiac lesions.

Evolution and emergence of primate-specific interferon regulatory factor 9

The binding of interferon (IFN) to its receptors leads to formation of IFN-stimulated gene factor 3 (ISGF3) complex that activates the transcription of cellular IFN-regulated genes. IFN regulatory factor 9 (IRF9, also called ISGF3γ or p48) is a key component of ISGF3. However, there is limited knowledge regarding the molecular evolution of IRF9 among vertebrates. In this study, we have identified the existence of the IRF9 gene in cartilaginous fish (sharks). Among primates, several isoforms unique to old world moneys and great apes are identified. These IRF9 isoforms are named as primate-specific IRF9 (PS-IRF9) to distinguish from canonical IRF9. PS-IRF9 originates from a unique exon usage and differential splicing in the IRF9 gene. Although the N-terminus are identical for all IRF9s, the C-terminal regions of the PS-IRF9 are completely different from canonical IRF9. In humans, two PS-IRF9s are identified and their RNA transcripts were detected in human primary peripheral blood mononuclear cells. In addition, human PS-IRF9 proteins were detected in human cell lines. Sharing the N-terminal exons with the canonical IRF9 proteins, PS-IRF9 is predicted to bind to the same DNA sequences as the canonical IRF9 proteins. As the C-terminal regions of IRFs are the determinants of IRF functions, PS-IRF9 may offer unique biological functions and represent a novel signaling molecule involved in the regulation of the IFN pathway in a primate-specific manner.

A report on the impact of rapid prenatal exome sequencing on the clinical management of 52 ongoing pregnancies: a retrospective review

OBJECTIVE

Studies have shown that prenatal exome sequencing (PES) improves diagnostic yield in cases of fetal structural malformation. We have retrospectively analysed PES cases from two of the largest fetal medicine centres in the UK to determine the impact of results on management of a pregnancy.

DESIGN

A retrospective review of clinical case notes.

SETTING

Two tertiary fetal medicine centres.

POPULATION

Pregnancies with fetal structural abnormalities referred to clinical genetics via a multidisciplinary team.

METHODS

We retrospectively reviewed the notes of all patients who had undergone PES. DNA samples were obtained via chorionic villus sampling or amniocentesis. Variants were filtered using patient-specific panels and interpreted using American College of Medical Genetics guidelines.

RESULTS

A molecular diagnosis was made in 42% (18/43) ongoing pregnancies; of this group, there was a significant management implication in 44% (8/18). A positive result contributed to the decision to terminate a pregnancy in 16% (7/43) of cases. A negative result had a significant impact on management in two cases by affirming the decision to continue pregnancy.

CONCLUSIONS

We demonstrate that the results of PES can inform pregnancy management. Challenges include variant interpretation with limited phenotype information. These results emphasise the importance of the MDT and collecting phenotype and variant data. As this testing is soon to be widely available, we should look to move beyond diagnostic yield as a measure of the value of PES.

TWEETABLE ABSTRACT

Prenatal exome sequencing can aid decision-making in pregnancy management; review ahead of routine implementation in NHS.

Biomarker changes associated with the development of resistance to aromatase inhibitors (AIs) in estrogen receptor-positive breast cancer

BACKGROUND

The purpose of this study was to identify any differences in key biomarkers associated with estrogen action between biopsies taken at diagnosis and at recurrence or progression during treatment with an aromatase inhibitor (AI).

PATIENTS AND METHODS

Patients were retrospectively identified from a clinical database as having relapsed or progressed during AI treatment. Immunohistochemistry was carried out against estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), insulin-like growth factor type-1 receptor (IGF1R), insulin receptor substrate-1 (IRS-1), stathmin, phosphatase and tensin homolog and Ki67.

RESULTS

Fifty-five pairs of samples were identified with ER- and/or PgR-positive diseases. Four (7%) patients were ER-negative at progression. Overall, PgR levels were lower in the recurrence sample, but 35% of cases remained positive. IGF1R levels decreased significantly. There were no substantial changes in HER2, IRS-1 or stathmin levels to indicate a role in resistance. Higher Ki67 levels at resistance indicate more proliferative disease.

CONCLUSIONS

The phenotype of AI-recurrent lesions shows high between-tumour heterogeneity. There is evidence of an increase in Ki67, a reduction in IGF1R and a loss of ER expression in some individuals and some activation of growth factor signalling pathways that may explain resistance in individuals and merit treatment targeted to those pathways. Biopsy at recurrence will be necessary to identify the relevant target for individuals.

Inter-rater reliability of the Pediatric Transplant Rating Instrument (P-TRI): challenges to reliably identifying adherence risk factors during pediatric pre-transplant evaluations

The purpose of this study was to assess the inter-rater reliability of the P-TRI, a 17-item instrument developed to identify risk factors associated with poor treatment adherence in pediatric solid organ transplant candidates. Because factors influencing treatment adherence may vary with age, the 89 subject samples were divided into pre-adolescent (0-11 yr) and adolescent (12-19 yr) groups. Each subject received two independent P-TRI ratings based on pretransplant psychosocial assessments separately conducted by a PSYC and a SWTC. Inter-rater reliability was assessed using the delta statistic. Overall, agreement was higher in the pre-adolescent group, with delta>0.70 for five items and delta<0.30 for two items. For the adolescent group, one item had a delta>0.70 and seven items had a delta<0.30. Overall, PSYC P-TRI ratings indicated fewer areas of concern on items assessing family dynamics compared with SWTC P-TRI ratings, whereas the reverse was true for items related to psychiatric history. Results highlight the challenges of conducting a reliable pretransplant assessment of adherence-related risk factors and suggest the need for revisions to the P-TRI prior to its use in clinical practice.

Targeting the receptor tyrosine kinase RET sensitizes breast cancer cells to tamoxifen treatment and reveals a role for RET in endocrine resistance

Endocrine therapy is the main therapeutic option for patients with estrogen receptor (ERalpha)-positive breast cancer. Resistance to this treatment is often associated with estrogen-independent activation of ERalpha. In this study, we show that in ERalpha-positive breast cancer cells, activation of the receptor tyrosine kinase RET (REarranged during Transfection) by its ligand GDNF results in increased ERalpha phosphorylation on Ser118 and Ser167 and estrogen-independent activation of ERalpha transcriptional activity. Further, we identify mTOR as a key component in this downstream signaling pathway. In tamoxifen response experiments, RET downregulation resulted in 6.2-fold increase in sensitivity of MCF7 cells to antiproliferative effects of tamoxifen, whereas GDNF stimulation had a protective effect against the drug. In tamoxifen-resistant (TAM(R)-1) MCF7 cells, targeting RET restored tamoxifen sensitivity. Finally, examination of two independent tissue microarrays of primary human breast cancers revealed that expression of RET protein was significantly associated with ERalpha-positive tumors and that in primary tumors from patients who subsequently developed invasive recurrence after adjuvant tamoxifen treatment, there was a twofold increase in the number of RET-positive tumors. Together these findings identify RET as a potentially important therapeutic target in ERalpha-positive breast cancers and in particular in tamoxifen-resistant tumors.

Changes in the Dynamic Relationship between ER and HER2 in Paired Breast Cancer (BC) Biopsies from Patients (Pts) with Recurrent Tamoxifen-Resistant Breast Cancer

Background: Paired biopsies at diagnosis and relapse on tamoxifen (TAM) provide information regarding adaptive changes associated with endocrine resistance. We previously reported that conversion to a HER2+ phenotype occurs infrequently1, however modest increases in HER2 may be relevant in the context of TAM resistance. Also while TAM resistance in general is associated with a fall in mean ER and PgR levels, this masks changes in individual pts.Aim: To determine whether a subset of HER2 negative BC demonstrated modest increases in HER2 by IHC and FISH, and if so whether this correlated with changes in ER and PgR expression in individual pts.Methods: Triplicate TMAs were constructed of paired primary and recurrent tumor samples from pts relapsing after adjuvant TAM. TMAs were stained for ER and HER2, whole sections for PgR. HER2 amplification was assessed by FISH.Results: Paired samples from primary and TAM-resistant recurrences were available on 53 ER+ and/or PgR+ pts. 10% had a HER2+ primary (IHC3+ and FISH+). 19% (10/53) showed increasing HER2 in the relapsed tumor (0 to 1+ in 5 pts, 1+ to 2+ in 2 pts and 0/1+ to 3+ in 3 pts). The 3 pts converting to 3+ also became FISH+. 71% (38/53) had stable or decreasing HER2. DFI was 50.3 months in the subset with stable or decreasing HER2, 40.2 in the subset with increasing HER2, and 35.2 in the HER2+ subset (p=NS). We next compared changes in ER and PgR in the 3 subsets. Among pts with stable or decreasing HER2 (N=38), there was a significant decrease in mean H-scores for both ER (p=0.001) and PgR (p=0.002) at relapse (Fig 1); the majority recurred with reduced ER (76%) or PgR levels (84%). In contrast, among pts with increasing HER2, there was no change in mean ER or PgR levels (Fig 2A); however when considering changes in individual pts, there was a balanced split between tumors relapsing with up- vs. down-regulation in ER/PgR (Fig 2B,C). In the HER2 positive subset, 100% of the pts relapsed with suppressed ER and PgR.Conclusion: In an updated series of TAM-resistant pts, we show that while conversions to HER2 3+/FISH+ remain rare (5%), modest increases in HER2 are more frequent (19%). TAM resistance in general is associated with decreasing ER and PgR. However, among pts with adaptive increases in HER2, TAM resistance is associated with either down- or up-regulation in ER expression and function. This is consistent with data from acquired endocrine resistance models we previously reported2,3.1Gutierrez et al, JCO 20052Pancholi et al, ERC 2008,3 Martin et al, JBC 2003

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 704.

ER and HER2 Expression Are POSITIVELY Correlated in HER2 Non-Over Expressing Breast Cancer

Aim: To determine the relationship between ER and HER2 expression according to HER2 amplification status.Background: ER and HER2 are the most commonly measured biomarkers in breast cancer and are important targets for therapy. It is known that ER and HER2 positivity are inversely correlated and that among ER+ tumours ER expression is higher in HER2 non-overexpressing (−ve) than HER2 overexpressing (+ve) disease (Konecny et al, JNCI 2003, 95: 142-53). There are however, very few data on the quantitative relationship between ER and HER2 expression in HER2−ve tumours. We therefore measured the expression of ER and HER2 at both the mRNA and protein level in HER2 +ve and −ve breast carcinomas.Methods: ER and HER2 levels were assessed by IHC (6F11 antibody and HercepTest, respectively) on tissue microarrays and q-RT-PCR in formalin-fixed primary breast cancers from 429 patients in the tamoxifen arm of the ABC Trial (ABC Trialists, JNCI 2007, 99: 506-15). HER2 amplification status was assessed with the PathVysion 2-probe FISH test. ER IHC was H-scored. Transcript levels for ER and HER2 from 1139 HER2−ve TransATAC tumours were available from the Oncotype DX test (Dowsett et al, Cancer Res 2009, 69suppl: 75s).Results: Matched results were available from all analyses for 257 ABC patients except for 25 cases where HER2 was by IHC or FISH. HER2 was amplified in 14.4% and equivocal in 1.3% of cases. ER was +ve in 67% of cases. The expected negative correlation between levels of ER and HER2 expression was found in HER2 +ve tumours (r=-0.45, p=0.0028). In contrast in HER2-ve tumours (ER+ve and ER-ve combined) there was a significant POSITIVE correlation between ER and HER2 mRNA levels (r=0.43, p&lt;0.0001). As a result in HER2−ve tumours the quantitative level of HER2 was higher in ER+ve than ER−ve tumours (mean fold difference 1.74, p&lt;0.0001). There was a mean 5.8-fold higher HER2 transcript levels in HER2+ve vs HER2−ve tumours in ER+ve disease and 12.9-fold higher in ER−ve disease. The positive correlation though weaker was maintained in the ER+ve HER2−ve group (r=0.24, p=0.0023) and was present to a similar extent in that subgroup in TransATAC (r=0.25, p&lt;0.00001). The positive association was also significant in ER IHC analyses in ABC: mean±95%CI H-scores were 90±19 and 134±19 in the 0 and 1+ HER2 IHC categories, respectively (p=0.0013).Conclusions: ER and HER2 expression are positively correlated at both protein and transcript levels in HER2−ve breast cancer in contrast to their negative correlation in HER2+ve disease. The distinction between HER2+ve and HER2−ve is greater in ER−ve than ER+ve disease and this may lead to greater diagnostic uncertainties in ER+ve patients. These findings may also have importance for signaling pathways and application of targeted therapy in HER2−ve disease.*Acknowledgement: We are grateful to the ABC Trial Working and Biological Studies Groups, the ATAC Trialists and Cancer Research UK for funding.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 703.

A Breast Cancer-Associated SNP Adjacent to ESR1 Correlates with Oestrogen Receptor-α (ERα) Level in Invasive Breast Tumours

Aim: To identify whether breast cancer-associated SNP rs2046210 is associated with ERα level in invasive breast tumours.BackgroundA recent genome-wide association study identified SNP rs2046210 at 6q25.1 as having a strong association with breast cancer risk1. The SNP is located 29kb upstream of the first untranslated exon of ESR1 and 180kb upstream of the transcription start site2. Rs2046210 is not in linkage disequilibrium (LD) with two of the most widely studied polymorphisms in ESR1. We test here the hypothesis that rs2046210 may be associated with altered ESR1 expression.MethodsPatients with both leukocyte DNA and invasive breast tumour paraffin blocks available were identified from two of our ongoing tissue collections: Femara Anastrazole Clinical Evaluation (FACE) and the British Breast Cancer (BBC) study. Germline DNA was extracted from bloods using the QIAamp DNA Blood Mini Kit. PCR was performed with primers spanning the SNP site, with a single basepair mismatch in the reverse sequence to generate an HhaI restriction site in the presence of the C allele. PCR product was run on a 3% agarose gel to confirm presence of a single 120bp band. Restriction digest with HhaI was then performed and products run on a 4% Metaphor agarose gel. Genotype was assigned as follows: 97bp band only = wild-type (C/C); 97bp and 120bp band = heterozygote (C/T); 120bp band only = variant (T/T). From corresponding invasive breast tumour, ERα was assessed on 4μm whole sections using clone 6F11 (Vector Labs) and quantified by H-score. Mean H-scores (left and right invasive breast tumours) were used for the BBC group. ERα- samples (H-score≤1.0) were excluded. Analysis was by ANOVA using non-parametric bias-corrected and accelerated 95% bootstrap confidence intervals (2000 replications), with genotype fitted as a score and study as a stratifying co-variate.ResultsH-score (mean) by genotypeStudyWild-typeHeterozygoteVariantFACE (n=280)171.8180.9184.9BBC (n=46)180.0178.9194.1Fitted mean172.6179.7186.7(% samples)(45)(44)(11) Minor allele frequency was 33%, which is similar to the 38% previously reported in patients of European ancestry1. Within FACE, increased ERα was seen with presence of variant SNP. In the BBC group, variant SNP patients had higher ERα than both wild-type and heterozygote. Overall, there was a significant difference in ERα score per genotype group of 7.05, (95% CI 0.7-13.5, p=0.035). This was circa 4% difference in H-score per variant allele.ConclusionThe variant genotype of SNP rs2046210 is associated with increased ERα expression. While the increase contributed by the variant allele is relatively modest, this may partly explain why the SNP is associated with increased breast cancer risk. Similar studies should be conducted in normal breast tissue.1Zheng et al. (2009) Nat. Gen. 41(3): 324-3282Kos et al. (2001) Mol. Endocrinol. 15: 2057-2063

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4138.

Phase 1b study of motesanib diphosphate (AMG 706) in combination with paclitaxel or docetaxel for the treatment of locally recurrent, unresectable or metastatic breast cancer

Abstract #4117

Background: Motesanib is a novel oral angiogenesis inhibitor designed to selectively target the tyrosine kinase activity of VEGF 1, 2 and 3; PDGF and Kit receptors. Here we report safety, preliminary efficacy and pharmacokinetics (PK) from an ongoing phase 1b dose-finding study of motesanib plus either paclitaxel (P) or docetaxel (D) in patients (pts) with advanced breast cancer.&#x2028; Methods: Eligible pts with ECOG 0 or 1 and ≤1 prior chemotherapy regimen for metastatic breast cancer received (until toxicity or disease progression) escalating doses of motesanib (50 or 125mg) QD orally continuously from day 3 of cycle 1 plus either P (Arm A) at 90mg/m2 on days 1, 8 and 15 of each 28-day cycle; or D (Arm B) at either 100mg/m2 on day 1 of every 21-day cycle or at 75mg/m2 with motesanib maximum tolerated dose (125mg QD). Objective response (OR) per RECIST was assessed every 8 (Arm A) or 6 wks (Arm B).&#x2028; Results: To date, 33 pts have received ≥1 dose of motesanib: Arm A, n=10; Arm B, n=23. Median age is 51 (range, 28-66) years. There were 5 DLTs (all grade 3) in 4 pts: abnormal liver function tests and deep vein thrombosis (Arm A, 125mg QD), fatigue (Arm A, 125mg QD), gallbladder enlargement (Arm B, 125mg QD+75mg/m2 D) and migraine (Arm B, 125mg QD). 28 pts (85%) had motesanib-related AEs; the most common were (worst grade): diarrhea, Arm A/B 60%/61% (grade 3, 0%/13%); fatigue, 30%/26% (grade 3, 10%/4%); hypertension, 20%/22% (grade 3, 10%/4%); and nausea, 10%/26% (no grade 3). Treatment-related AEs of interest in Arm A/B included epistaxis (10%/18%; all worst grade 1) and deep vein thrombosis (10%/0%; all worst grade 3). There were no grade 4 or 5 related AEs. Two deaths on study occurred (Arm B; 50 and 125mg QD n=1 each); both were not considered to be motesanib related. Motesanib PK parameters were generally within the range previously described for single-agent motesanib. PK profiles of P and D showed high interpatient variability, with AUC higher in some pts after motesanib coadministration. In pts with measurable disease at baseline (Arms A&B, n=7&18), best OR at time of last data cut-off was: confirmed PR in Arm A n=2 (29%), in Arm B n=5 (28%); SD in Arm A n=2 (29%), in Arm B n=9 (50%); durable SD ≥24 wks in Arm A n=0, in Arm B n=3 (17%). Median (range) duration of response currently is 169 (58-169) days in Arm A and 198 (96-337+) days in Arm B.&#x2028; Conclusions: Motesanib combined with P or D appears to be tolerable with evidence of antitumor activity in pts with advanced breast cancer. No marked effect on motesanib PK has been noted with coadministration of either P or D. Updated safety and efficacy data, including PFS, will be presented.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4117.

Safety-Related Knowledge and Behavior Changes in Participants of Farm Safety Day Camps

Significant resources are devoted to conducting farm safety day camps throughout North America, but the impact and effectiveness of these programs has not been systematically demonstrated. This project assessed changes in safety-related knowledge and behaviors among participants in the Progressive Farmer Farm Safety Day Camp program. A written pre-test and a three-month telephone post-test were administered to three samples of participants, ages 8 to 13, in camps held in 1999, 2000, and 2001. A sample of 20 to 30 camps was included in each year of the study, with a total sample of 1,780 participants for all three years. The pre-test and post-test contained questions related to first aid and to safety around animals, ATVs, farm equipment, flowing grains, and tractors. Three scores were computed from responses to 20 knowledge and behavior items. A knowledge score indicated the number of 8 knowledge items answered correctly, a behavior risk score indicated the amount of risk exposure for the child based on 8 behavior items, and an ATV safety gear risk score indicated, for those who rode ATVs, the level of risk due to lack of proper safety gear (4 items). From pre-test to post-test, there was an increase in knowledge scores and a decrease in behavior risk scores and ATV safety gear risk scores. These changes were consistent both for males and females, for farm residents and non-farm residents, and across all ages in the sample. These results support claims for the effectiveness of farm safety day camps for increasing knowledge and improving safe practices among camp participants.

RAGE and arthritis: the G82S polymorphism amplifies the inflammatory response

The receptor for advanced glycation end products (RAGE) and its proinflammatory S100/calgranulin ligands are enriched in joints of subjects with rheumatoid arthritis (RA) and amplify the immune/inflammatory response. In a model of inflammatory arthritis, blockade of RAGE in mice immunized and challenged with bovine type II collagen suppressed clinical and histologic evidence of arthritis, in parallel with diminished levels of TNF-alpha, IL-6, and matrix metalloproteinases (MMP) 3, 9 and 13 in affected tissues. Allelic variation within key domains of RAGE may influence these proinflammatory mechanisms, thereby predisposing individuals to heightened inflammatory responses. A polymorphism of the RAGE gene within the ligand-binding domain of the receptor has been identified, consisting of a glycine to serine change at position 82. Cells bearing the RAGE 82S allele displayed enhanced binding and cytokine/MMP generation following ligation by a prototypic S100/calgranulin compared with cells expressing the RAGE 82G allele. In human subjects, a case-control study demonstrated an increased prevalence of the 82S allele in patients with RA compared with control subjects. These data suggest that RAGE 82S upregulates the inflammatory response upon engagement of S100/calgranulins, and, thereby, may contribute to enhanced proinflammatory mechanisms in immune/inflammatory diseases.

Refining the DFNB7-DFNB11 deafness locus using intragenic polymorphisms in a novel gene, TMEM2

The combined DFNB7-DFNB11 deafness locus maps to chromosome 9q13-q21 between markers D9S1806 and D9S769. We have determined the cDNA sequence and genomic structure of a novel gene, TMEM2, that maps to this interval and is expressed in the cochlea. The mouse orthologue of this gene (Tmem2) maps to the murine dn (deafness) locus on mouse chromosome 19. Screens for transmembrane helices reveal the presence of at least one putative transmembrane domain in the TMEM2 protein. To determine whether mutations in TMEM2 cause hearing loss at the DFNB7-DFNB11 locus, we screened the coding region of this gene in DFNB7-DFNB11 affected families by direct sequencing. All DNA variants that segregated with the deafness and changed the predicted amino acid sequence of TMEM2 were common polymorphisms, as demonstrated by allele-specific amplification of pooled control DNA. Northern blot analysis showed no difference in transcript size or expression level of Tmem2 in dn/dn and control mice. The intragenic polymorphisms in TMEM2 represent a novel centromeric boundary for the DFNB7-DFNB11 interval.

RAGE mediates a novel proinflammatory axis: a central cell surface receptor for S100/calgranulin polypeptides

S100/calgranulin polypeptides are present at sites of inflammation, likely released by inflammatory cells targeted to such loci by a range of environmental cues. We report here that receptor for AGE (RAGE) is a central cell surface receptor for EN-RAGE (extracellular newly identified RAGE-binding protein) and related members of the S100/calgranulin superfamily. Interaction of EN-RAGEs with cellular RAGE on endothelium, mononuclear phagocytes, and lymphocytes triggers cellular activation, with generation of key proinflammatory mediators. Blockade of EN-RAGE/RAGE quenches delayed-type hypersensitivity and inflammatory colitis in murine models by arresting activation of central signaling pathways and expression of inflammatory gene mediators. These data highlight a novel paradigm in inflammation and identify roles for EN-RAGEs and RAGE in chronic cellular activation and tissue injury.

Identification and mutation analysis of a cochlear-expressed, zinc finger protein gene at the DFNB7/11 and dn hearing-loss loci on human chromosome 9q and mouse chromosome 19

The DFNB7/11 locus for autosomal recessive non-syndromic hearing loss (ARNSHL) has been mapped to an approx. 1.5 Mb interval on human chromosome 9q13-q21. We have determined the cDNA sequence and genomic structure of a novel cochlear-expressed gene, ZNF216, that maps to the DFNB7/11 interval. The mouse orthologue of this gene maps to the murine dn (deafness) locus on mouse chromosome 19. The ZNF216 gene is highly conserved between human and mouse, and contains two regions that show homology to the putative zinc linger domains of other proteins. To determine it mutations in ZNF216 might be the cause of hearing loss at the DFNB7/11 locus, we screened the coding region of this gene in DFNB7/11 families by direct sequencing. No potential disease-causing mutations were found. In addition, Northern blot analysis showed no difference in ZNF216 transcript size or abundance between dn and control mice. These data Suggest that the ZNF216 gene is unlikely to be responsible for hearing loss at the DFNB7/11 and dn loci.

Assembly of a high-resolution map of the Acadian Usher syndrome region and localization of the nuclear EF-hand acidic gene

Usher syndrome type 1C (USH1C) occurs in a small population of Acadian descendants from southwestern Louisiana. Linkage and linkage disequilibrium analyses localize USH1C to chromosome 11p between markers D11S1397 and D11S1888, an interval of less than 680 kb. Here, we refine the USH1C linkage to a region less than 400 kb, between genetic markers D11S1397 and D11S1890. Using 17 genetic markers from this interval, we have isolated a contiguous set of 60 bacterial artificial chromosomes (BACs) that span the USH1C critical region. Exon trapping of BAC clones from this region resulted in the recovery of an exon of the nuclear EF-hand acidic (NEFA) gene. However, DNA sequence analysis of the NEFA cDNA from lymphocytes of affected individuals provided no evidence of mutation, making structural mutations in the NEFA protein unlikely as the cellular cause of Acadian Usher syndrome.

The Hill reaction of chloroplasts isolated from glutaraldehyde-fixed spinach leaves

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