{"id":118,"date":"2011-03-05T21:39:22","date_gmt":"2011-03-05T21:39:22","guid":{"rendered":"http:\/\/stg-blogs.bmj.com\/jmg\/?p=118"},"modified":"2011-03-05T21:39:22","modified_gmt":"2011-03-05T21:39:22","slug":"kearns-sayre-syndrome-caused-by-defective-r1p53r2-assembly","status":"publish","type":"post","link":"https:\/\/stg-blogs.bmj.com\/jmg\/2011\/03\/05\/kearns-sayre-syndrome-caused-by-defective-r1p53r2-assembly\/","title":{"rendered":"Kearns-Sayre syndrome caused by defective R1\/p53R2 assembly"},"content":{"rendered":"<p><em>RRM2B<\/em> is a nuclear gene that encodes p53R2, a protein required for synthesising mitochondrial DNA (mtDNA). Accumulation of multiple mtDNA deletions in muscle and other tissues is a relatively frequent cause of mitochondrial disease in adults. Multiple mtDNA deletions arise because of faulty mtDNA replication, and we now show that 4% of 50 patients seen at our hospital with multiple mtDNA deletions had <em>RRM2B<\/em> mutations. One patient had Kearns-Sayre syndrome (KSS), which is usually a sporadic disorder; this is the first case to be linked to a nuclear gene defect. Identification of <em>RRM2B<\/em> mutations in patients with KSS when multiple mtDNA deletions are present is crucial for accurate genetic counselling. We also provide important insight into how <em>RRM2B<\/em> mutations cause disease by demonstrating impaired assembly of the p53R2 protein using the technique of Blue native gel electrophoresis. (By Dr Robert Pitceathly, <a href=\"http:\/\/jmg.bmj.com\/content\/early\/2011\/03\/04\/jmg.2010.088328.abstract?papetoc\">http:\/\/jmg.bmj.com\/content\/early\/2011\/03\/04\/jmg.2010.088328.abstract?papetoc<\/a>= )<!--TrendMD v2.4.8--><\/p>\n","protected":false},"excerpt":{"rendered":"<p>RRM2B is a nuclear gene that encodes p53R2, a protein required for synthesising mitochondrial DNA (mtDNA). Accumulation of multiple mtDNA deletions in muscle and other tissues is a relatively frequent cause of mitochondrial disease in adults. Multiple mtDNA deletions arise because of faulty mtDNA replication, and we now show that 4% of 50 patients seen [&#8230;]<\/p>\n<p><a class=\"btn btn-secondary understrap-read-more-link\" href=\"https:\/\/stg-blogs.bmj.com\/jmg\/2011\/03\/05\/kearns-sayre-syndrome-caused-by-defective-r1p53r2-assembly\/\">Read More&#8230;<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-118","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/stg-blogs.bmj.com\/jmg\/wp-json\/wp\/v2\/posts\/118","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/stg-blogs.bmj.com\/jmg\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/stg-blogs.bmj.com\/jmg\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/jmg\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/jmg\/wp-json\/wp\/v2\/comments?post=118"}],"version-history":[{"count":0,"href":"https:\/\/stg-blogs.bmj.com\/jmg\/wp-json\/wp\/v2\/posts\/118\/revisions"}],"wp:attachment":[{"href":"https:\/\/stg-blogs.bmj.com\/jmg\/wp-json\/wp\/v2\/media?parent=118"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/jmg\/wp-json\/wp\/v2\/categories?post=118"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/jmg\/wp-json\/wp\/v2\/tags?post=118"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}