Circular RNAs (circRNAs) are unique transcript isoforms characterized by back splicing of exon ends to form a covalently closed loop or circular conformation. These transcript isoforms are now known to be expressed in a variety of organisms across the kingdoms of life. Recent studies have shown the role of circRNAs in a number of diseases and increasing evidence points to their potential application as biomarkers in these diseases. We have created a comprehensive manually curated database of circular RNAs associated with diseases. This database is available at URL http://clingen.igib.res.in/circad/. The Database lists more than 1300 circRNAs associated with 150 diseases and mapping to 113 International Statistical Classification of Diseases (ICD) codes with evidence of association linked to published literature. The database is unique in many ways. Firstly, it provides ready-to-use primers to work with, in order to use circRNAs as biomarkers or to perform functional studies. It additionally lists the assay and PCR primer details including experimentally validated ones as a ready reference to researchers along with fold change and statistical significance. It also provides standard disease nomenclature as per the ICD codes. To the best of our knowledge, circad is the most comprehensive and updated database of disease associated circular RNAs. Availability: http://clingen.igib.res.in/circad/.

中文翻译：

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Circad：与疾病相关的环状RNA的全面手动管理资源。

环状RNA（circRNA）是独特的转录亚型，其特征是外显子末端的反向剪接形成共价闭合环或环状构象。现在已知这些转录亚型在整个生命王国的多种生物中表达。最近的研究表明，circRNA在许多疾病中的作用，越来越多的证据表明，它们在这些疾病中作为生物标志物的潜在应用。我们已经创建了与疾病相关的环状RNA的全面手动管理的数据库。该数据库位于URL http://clingen.igib.res.in/circad/。该数据库列出了1300多种与150种疾病相关的circRNA，并映射到113种国际疾病统计分类（ICD）代码，并具有与已发表文献相关的关联证据。该数据库在许多方面都是唯一的。首先，它提供了可以使用的引物，以便将circRNA用作生物标记或进行功能研究。此外，它还列出了测定和PCR引物的详细信息，包括经过实验验证的信息，以供研究人员参考，以及倍数变化和统计学意义。它还根据ICD代码提供标准的疾病命名法。据我们所知，circad是与疾病相关的环状RNA的最全面和最新的数据库。可用性：http：//clingen.igib.res.in/circad/。此外，它还列出了测定和PCR引物的详细信息，包括经过实验验证的信息，以供研究人员参考，以及倍数变化和统计学意义。它还根据ICD代码提供标准的疾病命名法。据我们所知，circad是与疾病相关的环状RNA的最全面和最新的数据库。可用性：http：//clingen.igib.res.in/circad/。此外，它还列出了测定和PCR引物的详细信息，包括经过实验验证的信息，以供研究人员参考，以及倍数变化和统计学意义。它还根据ICD代码提供标准的疾病命名法。据我们所知，circad是与疾病相关的环状RNA的最全面和最新的数据库。可用性：http：//clingen.igib.res.in/circad/。