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PubMed2006

INFO-RNA--a fast approach to inverse RNA folding.

MOTIVATION: The structure of RNA molecules is often crucial for their function. Therefore, secondary structure prediction has gained much interest. Here, we consider the inverse RNA folding problem, which means designing RNA sequences that fold into a given structure. RESULTS: We introduce a new algorithm for the inverse folding problem (INFO-RNA) that consists of two parts; a dynamic programming method for good initial sequences and a following improved stochastic local search that uses an effective neighbor selection method. During the initialization, we design a sequence that among all sequences adopts the given structure with the lowest possible energy. For the selection of neighbors during the search, we use a kind of look-ahead of one selection step applying an additional energy-based criterion. Afterwards, the pre-ordered neighbors are tested using the actual optimization criterion of minimizing the structure distance between the target structure and the mfe structure of the considered neighbor. We compared our algorithm to RNAinverse and RNA-SSD for artificial and biological test sets. Using INFO-RNA, we performed better than RNAinverse and in most cases, we gained better results than RNA-SSD, the probably best inverse RNA folding tool on the market. AVAILABILITY: www.bioinf.uni-freiburg.de?Subpages/software.html.

Algorithms↗
PubMed1998

The physiologic effects of inverse ratio ventilation.

STUDY OBJECTIVES: The efficacy of inverse ratio ventilation in ARDS is not clear. Furthermore, the mechanism responsible has not been determined. We designed an animal study to determine if inverse ratio ventilation improves gas exchange and by what mechanism. DESIGN: Prospective randomized, controlled design was used. SETTING: University of Missouri Pulmonary/Critical Care Animal Laboratory. PARTICIPANTS: Nine dogs with oleic acid-induced lung injury as control animals to assess stability of the model, nine in the experimental model. INTERVENTIONS: Conventional ventilation with full recruitment extrinsic positive end-expiratory pressure (PEEP) was compared with two other modes of ventilation. One was inverse ratio with extrinsic PEEP and the second was inverse ratio with intrinsic PEEP equal to full recruitment PEEP. Full recruitment levels of PEEP were defined by optimizing compliance, then increasing PEEP by 2.5 cm/H2O. Each type of ventilation was maintained for 45 min after the edema had stabilized. Comparison of lung injury over time requires stability of the model over time. Therefore, we also assessed the stability of the preparation over time by examining compliance, extravascular lung water, and venous admixture in nine control dogs with equivalent lung injury over the same time span. MEASUREMENTS AND RESULTS: Mean airway pressure was increased by both types of inverse ratio ventilation, while compliance remained stable. Venous admixture was reduced (conv=0.32+/-0.12, inverse ratio with extrinsic PEEP=0.24+/-0.10, inverse ratio with intrinsic PEEP=0.28+/-0.11) with inverse ratio with extrinsic PEEP, but the improvement was less with inverse ratio with intrinsic PEEP, even though the mean airway pressure was higher. CONCLUSIONS: We conclude that increasing mean airway pressure by prolongation of the inspiratory time improves gas exchange in our model of ARDS, but when mean airway pressure is increased further, allowing the development of intrinsic PEEP, the beneficial effects on gas exchange are less. Increasing mean airway pressure with intrinsic PEEP is not equivalent to other methods of increasing mean airway pressure.

Airway Resistance↗
PubMed2003

Development of an enhanced GFP-based dual-color reporter to facilitate genetic screens for the recovery of mutations in mice.

Mutagenesis screens to isolate a variety of alleles leading to null and non-null phenotypes represent an important approach for the characterization of gene function. Genetic schemes that use visible markers permit the efficient recovery of chemically induced mutations. We have developed a universal reporter system to visibly mark chromosomes for genetic screens in the mouse. The dual-color reporter is based on a single vector that drives the ubiquitous coexpression of the enhanced GFP (EGFP) spectral variants yellow and cyan. We show that widespread expression of the dual-color reporter is readily detected in embryonic stem cells, mice, and throughout developmental stages. CRE-loxP- and FLPe-FRT-mediated deletion of each color cassette demonstrates the modular design of the marker system. Random integration followed by plasmid rescue and sequence-based mapping was used to introduce the marker to a defined genomic location. Thus, single-step placement will simplify the construction of a genomewide bank of marked chromosomes. The dual-color nature of the marker permits complete identification of genetic classes of progeny as embryos or mice in classic regionally directed screens. The design also allows for more efficient and novel schemes, such as marked suppressor screens, in the mouse. The result is a versatile reporter that can be used independently or in combination with the growing sets of deletion and inversion resources to enhance the design and application of a wide variety of genetic schemes for the functional dissection of the mammalian genome.

Animals↗
PubMed2001

Patterns of DNA sequence variation in chromosomally recognized taxa of Anopheles gambiae: evidence from rDNA and single-copy loci.

Patterns of DNA sequence variation in the ribosomal DNA (rDNA) second internal transcribed spacer (ITS2) and five unlinked single-copy nuclear loci were examined for evidence of reproductive isolation among four chromosomally recognized taxa of Anopheles gambiae from West Africa: Savanna, Bamako, Mopti and Forest, as well as sibling species An. arabiensis and An. merus. Included among the single-copy loci were three sequence-tagged random amplified polymorphic DNA (RAPD) loci, two of which (R15 and R37) had been reported as discriminating between Mopti and other chromosomal forms. Each of the five single-copy sequences were highly polymorphic in most samples. However, the R15 and R37 loci had no diagnostic value, and therefore are not recommended as tools in recognition of field-collected An. gambiae chromosomal forms. Although pairwise comparisons between species generally revealed significant levels of differentiation at all five loci, variation was not partitioned by chromosomal form within An. gambiae at any single-copy locus examined. The few exceptions to these trends appear related to a location either inside or nearby chromosomal inversions. At the tryptophan oxygenase locus inside inversion 2Rb, variation was structured only by inversion orientation and not by taxonomic designation even between An. gambiae and An. arabiensis, providing the first molecular evidence that the 2Rb inversion was transferred between species by introgressive hybridization. By contrast, the rDNA showed fixed differences between species and a difference diagnostic for Mopti, consistent with effective, if not complete, reproductive isolation. The apparent disagreement between the data from this locus and multiple single-copy loci within An. gambiae may be explained by the much lower effective population size of rDNA, owing to concerted evolution, which confers increased sensitivity at much shorter divergence times. Taken together with the accompanying reports by della Torre et al. (2001), Favia et al. (2001) and Gentile et al. (2001), our data suggest that neutral molecular markers may not have the sensitivity required to detect isolation between these recently established taxa.

Animals↗
PubMed2001

Reduction of CSF and blood flow artifacts on FLAIR images of the brain with k-space reordered by inversion time at each slice position (KRISP).

BACKGROUND AND PURPOSE: Our purpose was to test a new variant of the fluid-attenuated inversion-recovery (FLAIR) sequence that was designed to reduce CSF and blood flow artifacts by use of a non-slice-selective inversion pulse and k-space reordered by inversion time at each slice position (KRISP). METHODS: With the KRISP FLAIR sequence, the slice order was cycled so that each inversion time (TI) was associated with a region of k-space rather than a particular slice, and the effective inversion time (TI(eff)) was chosen to null the signal from CSF. Scans were obtained with both conventional and KRISP FLAIR sequences. Studies were performed in 20 adult patients with a variety of brain diseases. Images were evaluated for artifacts from patient motion, CSF, and blood flow, and scored on a four-point scale. The conspicuity of the cortex, meninges, ventricular system, brain stem, and cerebellum was evaluated, as was lesion number and conspicuity. RESULTS: The KRISP FLAIR sequence showed more patient motion artifacts but had a pronounced advantage over the conventional sequence in control of CSF artifacts around the foramen of Munro, in the third ventricle, aqueduct, and fourth ventricle, as well as in the basal cisterns and around the brain stem and cerebellum. Blood flow artifacts from the internal carotid, basilar, and vertebral arteries were also much better controlled. Spurious high signal in the sylvian branches of the middle cerebral artery was eliminated. The meninges, cortex, ventricular system, brain stem, and cerebellum were better seen due to improved artifact suppression and an edge enhancement effect. CONCLUSION: The KRISP FLAIR sequence can suppress CSF and blood flow artifacts and improve the conspicuity of the meninges, cortex, brain stem, and cerebellum. Its major disadvantage is its duration, which may be reducible with a fast spin-echo version.

Adolescent↗
PubMed1990

Calcium and blood pressure. An epidemiologic perspective.

We reviewed the research literature on the epidemiologic relationship between blood pressure levels and calcium, with an emphasis on dietary intake. A conceptual framework for causal inference is summarized; then the designs and results of observational and intervention studies are presented. Of 25 reports of observational studies relating intake of calcium or calcium-rich foods to blood pressure, the majority found some evidence of an inverse association. However, many analyses did not support this relationship, and only two studies have confirmed the inverse association with a prospective design. Nineteen randomized controlled clinical trials of calcium supplementation have been reported, excluding those exclusively in pregnant women. Eleven of these showed no significant effects on blood pressure; in two trials, both systolic and diastolic pressure were significantly reduced; and in the remainder results were equivocal. Pooled analyses yielded estimates of a small (1.8 mm Hg), significant reduction in systolic blood pressure, but no effect on diastolic pressure. Epidemiologic relationships with serum and urinary calcium, and the possible mechanisms of these effects, are also discussed. We conclude that the evidence from studies in humans is suggestive, but not conclusive, regarding a role for calcium in hypertension. Recommendations for further epidemiologic studies are presented.

Blood Pressure↗
PubMed2001

Candidate foods in the Asia-Pacific region for cardiovascular protection: Oriental tea.

Chinese tea and the major health effects include: antimicrobial, anti-ultraviolet radiation, anticancer, lowering blood lipid and glucose, and protecting against coronary heart diseases. In contrast to the extensive studies on the protective effects of tea on cancer, fewer studies on the health effects of tea on cardiovascular diseases (CVD) have been published. This paper summarises the research results on the possible protective effects of tea on CVD available in China. The results from animal studies clearly demonstrated that tea pigments are effective in lowering blood lipid levels and preventing plaque formation in the aorta. However, the evidence of tea pigments in protecting ischemia heart disease (IHD) in humans is less convincing. One large well-designed ecological study reported an inverse correlation between tea drinking and IHD mortality; but the inverse correlation disappeared after controlling possible confounding factors. However, the effects in improving blood lipid levels and rheology biomarkers in hyperlipidemia subjects or CVD patients by tea pigments seem promising. However, these studies were not well-designed, controlled randomized clinical trials. This made the assessment difficult and inconclusive.

Animals↗
PubMed1997

Assembly and dissociation of human insulin and LysB28ProB29-insulin hexamers: a comparison study.

PURPOSE: Investigations into the kinetic assembly and dissociation of hexameric LysB28ProB29-human insulin (LysPro), a rapid-acting insulin analog produced by the sequence inversion of amino acids at positions B28 and B29, were designed to explain the impact that the sequence inversion has on the formulation and pharmacokinetics of the insulin analog. METHODS: The kinetics of phenolic ligand binding to human insulin and LysPro were studied by stopped-flow spectroscopy. The kinetics of R6 hexamer disruption were studied by extraction of Co(II) with EDTA. RESULTS: Phenolic ligand binding to human insulin yielded rate constants for a fast and slow phase that increased with increasing ligand concentration and are attributed to the T6 --> T3R3 and T3R3 --> R6 transitions, respectively. However, the kinetics of phenolic ligand binding with LysPro was dominated by rates of hexamer assembly. The kinetic differences between the insulin species are attributed to alterations at the monomer-monomer interface in the dimer subunit of the LysPro analog. The extraction of Co(II) from both hexameric complexes by EDTA chelation is slow at pH 8.0 and highly dependent on ligand concentration. Cobalt extraction from LysPro was pH dependent. Of the various phenolic ligands tested, the relative affinities for binding to the human and LysPro hexamer are resorcinol > phenol > m-cresol. CONCLUSIONS: The extraction data support the formation of an R6-type LysPro hexamer under formulation conditions, i.e., in the presence of divalent metal and phenolic ligand, that is similar in nature to that observed in insulin. However, the formation kinetics of LysPro identify a radically different monomeric assembly process that may help explain the more rapid pharmacokinetics observed with the hexameric formulation of LysPro insulin relative to human insulin.

Cobalt↗
PubMed1981

A pericentric inversion in the mouse.

A pericentric inversion induced in a Robertsonian chromosome was recovered and analyzed in a male heterozygous for the rearrangement. Identification was made from chromosome banding and confirmed by synaptonemal complex(SC) analyses. From the former, the chromosome was identified as Rb4Bnr. The inversion involves about 34% of the chromosome length, and is designated In(11.13LS)29Rk. Analysis of SC inversion loops gave break points at 0.20 in the short arm and 0.54 in the long arm. Inhibition of homologous synapsis in the inversion was observed at zygotene and early pachytene, while synaptic adjustment was found to lead to heterologous SC formation at late pachytene. The inversion is believed to be causally related to the reduction in fertility observed in the carriers.

Animals↗
PubMed2006

[A method using long primers for cloning the upstream sequence of delta-6 fatty acid desaturases gene of Thamnidium elegans by nested inverse PCR].

Thamnidium elegans is a kind of phycomycete that produces essential unsaturated fatty acids, particularly y-linolenic acid. In this process, delta6-Fatty acid desaturase (D6D) plays a key role due to its enzymatic properties that catalyze the delta6 site dehydrogenation of precursor linoleic acid (18:2delta(9, 12) n-6) and a-linolenic acid (18:3delta(9, 12, 15) n-3). This reaction is the first and rate-limiting step of highly unsaturated fatty acids (HUFA) synthesis pathways. After we have isolated and cloned the gene coding delta6-fatty acid desaturase from Thamnidium elegans As3.2806 (GenBank accession number DQ099380), our interest focuses on the promotion and regulation of the gene transcription. To achieve this aim, we designed long primers and used nested inverse PCR to amplify DNA flanking sequences. First, genome of Thamnidium elegans was extracted and digested with restriction enzymes EcoR I and Kpn I , respectively. Then we ligated the digested DNA with T4 ligase at low concentration which is propitious for linear DNA to joint intromolecule. According to the sequence of delta6-fatty acid desaturase gene of Thamnidium elegans, we designed a couple of 35nt long inverse primers and two couples of shorter inverse primers for inverse PCR. Three rounds of PCR reactions were performed. In the primary reaction, the ligated DNA was used as a template, and the product was used as the template of the secondary reaction, the tertiary reaction was achieved in the same way. After all the three rounds of reactions, we got a nice product about 4 kb from the EcoR I digested sample, in which a 1.3kb 5' upstream sequence (GenBank accession number DQ309425) of delta6-fatty acid desaturase gene containing several putative regulatory elements including TATA. box, FSE-2, AP-1 sites, CCAAT cis-element site and STRE-binding site was derived after sequencing. All of these implied intensely that this 1.3kb fragment is a condition-regulated promoter. It is the first report about Thamnidium elegans detla6-fatty acid desaturase gene promoter. The procedure described here is a rapid and simple method and particularly useful to isolate flanking sequences from fungal genome. box, FSE-2, AP-1 sites, CCAAT cis-element site and STRE-binding site was derived after sequencing. All of these implied intensely that this 1.3 kb fragment is a condition-regulated promoter. It is the first report about Thamnidium elegans delta6-fatty acid desaturase gene promoter. The procedure described here is a rapid and simple method and particularly useful to isolate flanking sequences from fungal genome.

Base Sequence↗
PubMedDate not supplied

Relation of physical activity and cardiovascular fitness to coronary heart disease, Part I: A meta-analysis of the independent relation of physical activity and coronary heart disease.

BACKGROUND: This paper is the first of two reports that together review the scientific evidence regarding the inverse relation between physical activity and cardiovascular fitness and coronary heart disease (CHD). METHODS: In Part I, the evidence suggesting a causal link between physical activity and CHD protection independent of other CHD risk factors is reviewed, accounting for bias, confounding, and different study designs. RESULTS: A strong, consistent inverse relation is found. Using meta-analytic techniques, the relative risk of the independent relation of physical inactivity to CHD is 1.37, with a 95 percent confidence interval (1.27-1.48). CONCLUSIONS: A graded biologic response of CHD protection to physical activity is shown, but the intensity, duration, and frequency of activity necessary for CHD benefit remain unclear. Plausible biologic mechanisms for the inverse relation of physical activity to CHD are the risk factor modifications that accrue with physical activity.

Causality↗
PubMed2002

Quantifying uncertainty in geoacoustic inversion. II. Application to broadband, shallow-water data.

This paper applies the new method of fast Gibbs sampling (FGS) to estimate the uncertainties of seabed geoacoustic parameters in a broadband, shallow-water acoustic survey, with the goal of interpreting the survey results and validating the method for experimental data. FGS applies a Bayesian approach to geoacoustic inversion based on sampling the posterior probability density to estimate marginal probability distributions and parameter covariances. This requires knowledge of the statistical distribution of the data errors, including both measurement and theory errors, which is generally not available. Invoking the simplifying assumption of independent, identically distributed Gaussian errors allows a maximum-likelihood estimate of the data variance and leads to a practical inversion algorithm. However, it is necessary to validate these assumptions, i.e., to verify that the parameter uncertainties obtained represent meaningful estimates. To this end, FGS is applied to a geoacoustic experiment carried out at a site off the west coast of Italy where previous acoustic and geophysical studies have been performed. The parameter uncertainties estimated via FGS are validated by comparison with: (i) the variability in the results of inverting multiple independent data sets collected during the experiment; (ii) the results of FGS inversion of synthetic test cases designed to simulate the experiment and data errors; and (iii) the available geophysical ground truth. Comparisons are carried out for a number of different source bandwidths, ranges, and levels of prior information, and indicate that FGS provides reliable and stable uncertainty estimates for the geoacoustic inverse problem.

Acoustics↗
PubMed1999

An alternative inverse PCR (IPCR) method to amplify DNA sequences flanking Tn5 transposon insertions.

We have developed an alternative method to amplify DNA sequences flanking Tn5 transposon insertions. This method relies on the identical sequences of inverted terminal repeats, located at the 5' and 3' ends of Tn5, to determine the location and orientation of a transposon insertion within a restriction endonuclease fragment. From this information, PCR primers can be designed to selectively amplify by inverse PCR the DNA flanking one side of the transposon. This method avoids the problem of amplifying or cloning long sequences flanking Tn5. To demonstrate the applicability of this method, we generated Tn5 transposon mutants of Pseudomonas abietaniphila BKME-9 which no longer grew on dehydroabietic acid (DhA). The flanking sequence of one of the mutant (strain BKME-941) which accumulated 7-oxoDhA, was amplified.

Abietanes↗
PubMed2002

Inverse laminoplasty for the treatment of lumbar spinal stenosis.

STUDY DESIGN: Fifteen patients with lumbar spinal stenosis were treated by a new technique, inverse laminoplasty, and the results were evaluated clinically and radiologically. OBJECTIVE: To present the advantages of inverse laminoplasty over laminectomy for the treatment of lumbar spinal stenosis. SUMMARY AND BACKGROUND DATA: Laminectomy has been used widely in the treatment of lumbar spinal stenosis. Destruction of the spinal bony structure, instability, and peridural scar formation are the main problems with this procedure. To overcome these disadvantages, a practical technique is presented here. MATERIAL AND METHODS: In a prospective study, 15 patients who underwent surgery with the inverse laminoplasty technique were evaluated clinically and radiologically. The Oswestry Disability Index was used for clinical assessment. L4-L5 spinal stenosis was detected in all patients. As the operative technique, the L4 lamina was elevated en bloc using a high-speed drill and rongeur. After removal of the ligamentum flavum, the roof of the foramina, and/or disc, the lamina was rotated 180 degrees, rested on facets, and reattached by use of a titanium miniplate. RESULTS: All patients improved clinically and neurologically after this procedure. The mean Oswestry Disability Score was 38.33 preoperatively and 7.0 postoperatively. The mean follow-up time was 17.3 months. Spinal canal diameters were calculated by preoperative and postoperative computed tomography, and the mean enlargement was 77.8%. No complications were observed. CONCLUSION: With this technique, the important integrity of the spinal osseous structures is preserved, and a significant enlargement of the spinal canal area is achieved. This technique prevents peridural scar formation after laminectomy caused by a mechanical barrier effect. Long-term follow-up is needed to evaluate spinal stability in these patients.

Adolescent↗
PubMed2003

Penetrating corneal transplant with inadvertent corneal button inversion.

PURPOSE: To report a penetrating corneal transplant in which there was inadvertent inversion of the corneal button. DESIGN: Interventional case report. METHODS: A 48-year-old man with lattice corneal dystrophy had a third penetrating keratoplasty in the right eye 3 years after the second procedure and 2 years following renal transplantation. RESULTS: Histologic examination of the corneal button from the second penetrating keratoplasty disclosed inadvertent corneal graft inversion. Survival epithelium from the donor in the anterior chamber may be explained by the ocular anterior chamber-associated immune deviation or by the patient's systemic cyclosporine A (CsA) treatment after renal transplantation. CONCLUSIONS: Histologically proven corneal button inversion is a rare cause of corneal graft failure.

Cornea↗
PubMed2000

Effects of tape and exercise on dynamic ankle inversion.

OBJECTIVE: To compare the effects of tape, with and without prewrap, on dynamic ankle inversion before and after exercise. DESIGN AND SETTING: Doubly multivariate analyses of variance were used to compare the taping and exercise conditions. Subjects were randomly assigned to a fixed treatment order as determined by a balanced latin square. The independent variables were tape application (no tape, tape with prewrap, tape to skin) and exercise (before and after). The dependent variables were average inversion velocity, total inversion, maximum inversion velocity, and time to maximum inversion. SUBJECTS: Thirty college-age male and female students (17 males, 13 females; mean age = 24.9 +/- 4.3 years, range, 19 to 39 years) were tested. Subjects were excluded from the study if they exhibited a painful gait or painful range of motion or had a past history of ankle surgery or an ankle sprain within the past 4 weeks. MEASUREMENTS: We collected data using electronic goniometers while subjects balanced on the right leg on an inversion platform tilted about the medial-lateral axis to produce 15 degrees of plantar flexion. Sudden ankle inversion was induced by pulling the inversion platform support, allowing the platform support base to rotate 37 degrees . Ten satisfactory trials were recorded on the inversion platform before and after a prescribed exercise bout. We calculated total inversion, time to maximum inversion, average inversion velocity, and maximum inversion velocity after sudden inversion. RESULTS: We found no significant differences between taping to the skin and taping over prewrap for any of the variables measured. There were significant differences between both taping conditions and no-tape postexercise for average inversion velocity, maximum inversion, maximum inversion velocity, and time to maximum inversion. The total inversion mean for no-tape postexercise was 38.8 degrees +/- 6.3 degrees , whereas the means for tape and skin and for tape and prewrap were 28.3 degrees +/- 4.6 degrees and 29.1 degrees +/- 4.7 degrees , respectively. After exercise, inversion increased by 1.0 degrees +/- 2.8 degrees for the no-tape condition, whereas the tape-to-skin and tape-over-prewrap inversion increased by 2.1 degrees +/- 3.2 degrees and 1.7 degrees +/- 2.2 degrees , respectively. CONCLUSIONS: There was no difference in the amount of inversion restriction when taping with prewrap was compared with taping to the skin. Tape and tape with prewrap significantly reduced the average inversion velocity, maximum inversion, maximum inversion velocity, and the time to maximum inversion. Both taping conditions offered residual restriction after exercise.

Journal Article↗
PubMed2005

Optimal design of loudspeaker arrays for robust cross-talk cancellation using the Taguchi method and the genetic algorithm.

An optimal design technique of loudspeaker arrays for cross-talk cancellation with application in three-dimensional audio is presented. An array focusing scheme is presented on the basis of the inverse propagation that relates the transducers to a set of chosen control points. Tikhonov regularization is employed in designing the inverse cancellation filters. An extensive analysis is conducted to explore the cancellation performance and robustness issues. To best compromise the performance and robustness of the cross-talk cancellation system, optimal configurations are obtained with the aid of the Taguchi method and the genetic algorithm (GA). The proposed systems are further justified by physical as well as subjective experiments. The results reveal that large number of loudspeakers, closely spaced configuration, and optimal control point design all contribute to the robustness of cross-talk cancellation systems (CCS) against head misalignment.

Algorithms↗
PubMed2006

Genetic reproductive risk in inversion carriers.

OBJECTIVE: To evaluate the risk of four inversion carriers for producing unbalanced gametes. DESIGN: Prospective analysis of sperm nuclei by fluorescence in situ hybridization (FISH). SETTING: Universitat Autònoma de Barcelona. PATIENT(S): Four inversion carriers. INTERVENTION(S): A semen sample from each patient was collected and prepared for FISH. MAIN OUTCOME MEASURE(S): The segregation outcome of each inversion was analyzed. The presence of interchromosomal effects (ICE) on chromosomes 13, 18, 21, X, and Y was also evaluated. RESULT(S): A variable production of unbalanced gametes, which implies a heterogeneous behavior of the inversions, was detected. This variability seems to be directly related to the size of the inversion, indicating that the production of recombinant gametes in inversion carriers would not be relevant when the inverted segment is smaller than 100 Mbp. CONCLUSION(S): Inversions have a well-defined reproductive effect on carriers. Carriers of inversions up to 100 Mbp have a low [corrected] reproductive risk and would not usually benefit from preimplantation genetic diagnosis.

Adult↗