A systematic review to assess the utility of genomic autopsy using exome or genome sequencing in cases of congenital anomalies and perinatal death.

PURPOSE: Exome or genome sequencing (ES or GS) can identify genetic causes of otherwise unexplained congenital anomaly and perinatal death (PND) but is not routine practice. The evidence base for "genomic autopsy" after termination of pregnancy for fetal anomaly (TOPFA) and PND has been synthesized to determine the value of this investigation. METHODS: We conducted a systematic review and meta-analysis of studies meeting prespecified inclusion criteria and containing ≥10 cases of TOPFA or PND (with or without major congenital abnormality), in which ES or GS was conducted. We determined test performance, including diagnostic yield, accuracy, and reliability. We also reported outcomes associated with clinical utility and harms, where described. RESULTS: From 2245 potentially eligible studies, 32 publications were eligible and had data extracted, representing 2120 cases that could be meta-analyzed. No diagnostic accuracy or comparative studies were identified, although some analysis of concordance between different ES/GS methodologies could be performed. Studies reporting parent-related outcomes or long-term follow-up did not do so in a systematic or quantifiable manner. CONCLUSION: Evidence suggests that approximately one-fourth to one-third of fetal losses associated with TOPFA or unexplained PND are associated with a genetic cause identifiable on ES or GS-albeit this estimate varies depending on phenotypic and background risk factors. Despite the large body of evidence on ES and GS, little research has attempted to validate the accuracy of testing, nor measure the clinical or societal outcomes in families that follow the diagnostic investigation in this context.

Neglected impacts of patient decision-making associated with genetic testing.

We highlight non-health-related impacts associated with genetic testing (GT) and knowing one's genetic status so that health technology assessment (HTA) analysts and HTA audiences may more appropriately consider the pros and cons of GT. Whereas health-related impacts of GT (e.g., increased healthy behaviors and avoidance of harms of unnecessary treatment) are frequently assessed in HTA, some non-health-related impacts are less often considered and are more difficult to measure. This presents a challenge for accurately assessing whether a genetic test should be funded. In health systems where HTA understandably places emphasis on measurable clinical outcomes, there is a risk of creating a GT culture that is pro-testing without sufficient recognition of the burdens of GT. There is also a risk of not funding a genetic test that provides little clinical benefit but nonetheless may be seen by some as autonomy enhancing. The recent development of expanded HTA frameworks that include ethics analyses helps to address this gap in the evidence and bring awareness to non-health-related impacts of GT. The HTA analyst should be aware of these impacts, choose appropriate frameworks for assessing genetic tests, and use methods for evaluating impacts. A new reporting tool presented here may assist in such evaluations.

Diagnostic performance of serum cobalamin tests: a systematic review and meta-analysis.

AIMS: Serum cobalamin (cbl, vitamin B(12)) tests are routinely ordered for investigating conditions potentially amenable to cbl supplementation. This study aimed to systematically assess the evidence of diagnostic accuracy for serum cbl tests across patient subgroups. METHODS: Seven medical databases were searched (1990 to November 2009). Studies were included that compared serum cbl to a reference standard (all reference standards employed). Study quality was assessed using QUADAS. Summary estimates of test performance were determined using the bivariate model and hierarchical summary receiver operating characteristic curves (HSROC). RESULTS: Of 2878 identified studies, 54 were included. Studies rated poorly against QUADAS criteria. Positive (PLR) and negative likelihood ratios (NLR) were 2.72 [95% confidence interval (CI) 1.95, 3.81] and 0.59 (0.49, 0.72), respectively (studies employing methylmalonic acid as the referent). In studies employing a clinical reference standard, PLR was 3.33 (0.92, 12.10) and NLR 0.34 (0.13, 0.89). Test performance did not vary by clinical indication, test method or age. CONCLUSION: This review was limited by the quality of the evidence base and lack of a gold standard. From the available evidence, diagnosis of conditions amenable to cbl supplementation on the basis of serum cbl level alone cannot be considered a reliable approach to investigating suspected vitamin deficiency.

Cell division requires a direct link between microtubule-bound RacGAP and Anillin in the contractile ring.

The mitotic microtubule array plays two primary roles in cell division. It acts as a scaffold for the congression and separation of chromosomes, and it specifies and maintains the contractile-ring position. The current model for initiation of Drosophila and mammalian cytokinesis [1-5] postulates that equatorial localization of a RhoGEF (Pbl/Ect2) by a microtubule-associated motor protein complex creates a band of activated RhoA [6], which subsequently recruits contractile-ring components such as actin, myosin, and Anillin [1-3]. Equatorial microtubules are essential for continued constriction, but how they interact with the contractile apparatus is unknown. Here, we report the first direct molecular link between the microtubule spindle and the actomyosin contractile ring. We find that the spindle-associated component, RacGAP50C, which specifies the site of cleavage [1-5], interacts directly with Anillin, an actin and myosin binding protein found in the contractile ring [7-10]. Both proteins depend on this interaction for their localization. In the absence of Anillin, the spindle-associated RacGAP loses its association with the equatorial cortex, and cytokinesis fails. These results account for the long-observed dependence of cytokinesis on the continual presence of microtubules at the cortex.