Departments of Pediatrics University of Minnesota, Minneapolis, USA.
Genet Med. 2011 Dec;13(12):1006-10. doi: 10.1097/GIM.0b013e318226fc2e.
: Bedside newborn hearing screening is highly successful in identifying deaf or hard-of-hearing infants. However, newborn hearing screening protocols have high loss to follow-up rates. We propose that bloodspot-based genetic testing for GJB2 alleles can provide a means for rapid confirmation in a subset of infants who fail bedside newborn hearing screening.
: We performed a case-control study comparing the prevalence of common GJB2 mutations from deidentified bloodspots designated as "refer" by newborn hearing screening and contemporaneously selected randomly chosen controls designated as "pass." Between March 2006 and December 2007, 2354 spots were analyzed for common alleles, c.35delG, c.167delT, c.235delC, and p.V37I in GJB2 with a subset reanalyzed by conventional Sanger sequencing to search for additional alleles.
: The prevalence of biallelic GJB2 mutations in bloodspots from infants who referred by newborn hearing screening is approximately 1 in 50 (23/1177). In contrast, one bloodspot from an infant who passed newborn hearing screening was identified to harbor biallelic GJB2 mutations.
: These findings show that when a newborn refers by newborn hearing screening, there is a significant chance that GJB2-related hearing loss is present. Bloodspot-based genetic testing for common GJB2 alleles should be considered as second tier testing for bedside newborn hearing screening.
床边新生儿听力筛查在识别聋或重听婴儿方面非常成功。然而，新生儿听力筛查方案的失访率很高。我们提出，基于血斑的 GJB2 等位基因突变检测可以为床边新生儿听力筛查失败的一部分婴儿提供快速确认的方法。
我们进行了一项病例对照研究，比较了通过床边新生儿听力筛查被指定为“转诊”的血斑与同时选择的被指定为“通过”的随机对照血斑中常见 GJB2 突变的患病率。在 2006 年 3 月至 2007 年 12 月期间，分析了 2354 个血斑中 GJB2 常见等位基因 c.35delG、c.167delT、c.235delC 和 p.V37I 的情况，其中一部分通过常规 Sanger 测序重新分析，以寻找其他等位基因。
在通过床边新生儿听力筛查转诊的婴儿的血斑中，双等位基因突变的患病率约为 1/50（23/1177）。相比之下，通过床边新生儿听力筛查的一名婴儿的一个血斑被确定为携带有双等位基因突变的 GJB2。
这些发现表明，当新生儿通过床边新生儿听力筛查转诊时，GJB2 相关听力损失的可能性很大。基于血斑的常见 GJB2 等位基因突变检测应被视为床边新生儿听力筛查的二线检测。
