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We have developed a new strategy for de novo prediction of splice junctions in short-read RNA-seq data, suitable for detection of novel splicing events and chimeric transcripts. When tested on mouse RNA-seq data, > 31,000 splice events were predicted, of which 88% bridged between two regions separated by <= 100 kb, and 74% connected two exons of the same RefSeq gene. Our method also reports genomic rearrangements such as insertions and deletions.

There is a group of proteins that are encoded by a single gene,   expressed as a single precursor protein and dually targeted to both   mitochondria and chloroplasts using an ambiguous targeting peptide.   Sequence analysis of 43 dual targeted proteins in comparison with 385   mitochondrial proteins and 567 chloroplast proteins of Arabidopsis   thaliana revealed an overall significant increase in phenylalanines,   leucines, and serines and a decrease in acidic amino acids and glycine   in dual targeting peptides (dTPs). The N-terminal portion of dTPs has   significantly more serines than mTPs. The number of arginines is   similar to those in mTPs, but almost twice as high as those in cTPs. We   have investigated targeting determinants of the dual targeting peptide   of Thr-tRNA synthetase (ThrRS-dTP) studying organellar import of N- and   C-terminal deletion constructs of ThrRS-dTP coupled to GFP. These   results show that the 23 amino acid long N-terminal portion of   ThrRS-dTP is crucial but not sufficient for the organellar import. The   C-terminal deletions revealed that the shortest peptide that was   capable of conferring dual targeting was 60 amino acids long. We have   purified the ThrRS-dTP(2-60) to homogeneity after its expression as a   fusion construct with GST followed by CNBr cleavage and ion exchange   chromatography. The purified ThrRS-dTP(2-60) inhibited import of   pF(1)beta into mitochondria and of pSSU into chloroplasts at mu M   concentrations showing that dual and organelle-specific proteins use   the same organellar import pathways. Furthermore, the CD spectra of   ThrRS-dTP(2-60) indicated that the peptide has the propensity for   forming alpha-helical structure in membrane mimetic environments;   however, the membrane charge was not important for the amount of   induced helical structure. This is the first study in which a dual   targeting peptide has been purified and investigated by biochemical and   biophysical means.

Cervical cancer is strongly associated with infection by oncogenic forms of human papillomavirus (HPV), mainly HPV 16 and HPV 18. The aim of this study was to test if a locus previously mapped to a region on chromosome 17 qter in patients with epidermodysplasia verucciformis (EV) and psoriasis and considered to be responsible for an increased susceptibility to HPV 5, also is linked to increased HPV susceptibility in cervical cancer in situ. We also wanted to test whether HPV 16 positivity cluster in families with cervical cancer. DNA was extracted from formalin fixed biopsies of 224 affected from 77 families diagnosed with cervical cancer in situ. Two microsatellite markers (D17S939 and D17S802) containing the locus were genotyped and linkage analysis was performed. No linkage was found to any of the two markers, neither when considering all cancer cases as affected nor when only considering HPV 16 infected cancer cases as affected in the analysis. We conclude that the susceptibility locus for HPV 5 infections associated with EV and psoriasis does not seem to affect susceptibility to HPV 16, frequently detected in cervical cancer. Also, positivity for HPV 16 did not show a significant clustering in families.

Waist-hip ratio (WHR) is a measure of body fat distribution and a predictor of metabolic consequences independent of overall adiposity. WHR is heritable, but few genetic variants influencing this trait have been identified. We conducted a meta-analysis of 32 genome-wide association studies for WHR adjusted for body mass index (comprising up to 77,167 participants), following up 16 loci in an additional 29 studies (comprising up to 113,636 subjects). We identified 13 new loci in or near RSPO3, VEGFA, TBX15-WARS2, NFE2L3, GRB14, DNM3-PIGC, ITPR2-SSPN, LY86, HOXC13, ADAMTS9, ZNRF3-KREMEN1, NISCH-STAB1 and CPEB4 (P = 1.9 × 10⁻⁹ to P = 1.8 × 10⁻⁴⁰) and the known signal at LYPLAL1. Seven of these loci exhibited marked sexual dimorphism, all with a stronger effect on WHR in women than men (P for sex difference = 1.9 × 10⁻³ to P = 1.2 × 10⁻¹³). These findings provide evidence for multiple loci that modulate body fat distribution independent of overall adiposity and reveal strong gene-by-sex interactions.

Cervical cancer is caused by persistent infection of oncogenichuman papillomavirus (HPV). Most infected women clear the viruswithout developing cervical lesions and it is likely that immunologicalhost factors affect susceptibility to cervical cancer. Theimpact of the human leukocyte antigen (HLA) locus on the risk ofcervical cancer is established and several other genes involved inimmunological pathways have been suggested as biologically plausiblecandidates. The aim of this study was to examine the potentialrole of polymorphisms in 4 candidate genes by analysis of1,306 familial cervical cancer cases and 288 controls. The followinggenes and polymorphisms were studied: Chemokine receptor2 (CCR-2) V64I; Interleukin 4 receptor a (IL-4R) I75V, S503P andQ576R; Interleukin 10 (IL-10) 2592; and Fas ligand (FasL) 2844.The CCR-2 64I variant was associated with decreased risk of cervicalcancer; homozygote carriers of the 64I variant had an oddsratio of 0.31 (0.12–0.77). This association was detected in both carriersand noncarriers of the HLA DQB1*0602 cervical cancer riskallele. The IL-4R 75V variant was associated with increased riskof cervical tumors, cases homozygote for 75V had an odds ratio of1.91 (1.27–2.86) with a tendency that the association was strongerin noncarriers of the DQB1*0602 allele. We did not find any associationfor IL-10 2592, or FasL 2844, previously reported to beassociated with cervical cancer in the Dutch and Chinese populations,respectively.

Copy number variation (CNV) comprises a recently discovered kind of variation involving deletion and duplication of DNA segments of variable size, ranging from a few hundred basepairs to several million. By altering gene dosage levels or disrupting proximal or distant regulatory elements CNVs create human diversity. They represent also an important factor in human evolution and play a role in many disorders including cancer. Array-based comparative genomic hybridization as well as expression arrays are powerful and suitable methods for determination of copy number variations or gene expression changes in the human genome. In paper I we established a 32K clone-based genomic array, covering 99% of the current assembly of the human genome with high resolution and applied it in the profiling of 71 healthy individuals from three ethnic groups. Novel and previously reported CNVs, involving ~3.5% of the genome, were identified. Interestingly, 87% of the detected CNV regions overlapped with known genes indicating that they probably have phenotypic consequences. In papers II through IV we applied this platform to different tumor types, namely two collections of brain tumors, glioblastoma (paper II) and medulloblastoma (paper III), and a set of bladder carcinoma (paper IV) to identify chromosomal alterations at the level of DNA copy number that could be related to tumor initiation/progression. Tumors of the central nervous system represent a heterogeneous group of both benign and malignant neoplasms that affect both children and adults. Glioblastoma and medulloblastoma are two malignant forms. Glioblastoma often affects adults while the embryonal tumor medulloblastoma is the most common malignant brain tumor among children. The detailed profiling of 78 glioblastomas, allowed us to identify a complex pattern of aberrations including frequent and high copy number amplicons (detected in 79% of samples) as well as a number of homozygously deleted loci. These regions encompassed not only previously reported oncogenes and tumor suppressor genes but also numerous novel genes. In paper III, a subset of 26 medulloblastomas was analyzed using the same genomic array. We observed that alterations involving chromosome 17, especially isochromosome 17q, were the most common genomic aberrations in this tumor type, but copy number alterations involving other chromosomes: 1, 7 and 8 were also frequent. Focal amplifications, on chromosome 1 and 3, not previously described, were also detected. These loci may encompass novel genes involved in medulloblastoma development. In paper IV we examined for the presence of DNA copy number alterations and their effect on gene expression in a subset of 21 well-characterized Ta bladder carcinomas, selected for the presence or absence of recurrences. We identified a number of novel genes as well as a significant association between amplifications and high-grade and recurrent tumors which might be clinically useful.

The results derived from these studies increase our understanding of the genetic alterations leading to the development of these tumor forms and point out candidate genes that may be used in future as targets for new diagnostic and therapeutic strategies.