Any unwanted regions for primer design in sequences can be masked using a pair of "" to keep the sequence unchanged ()

Alternatively, the unwanted regions can be replaced with "Ns" (). The included region can be specified by one pair "{}" and only one included region can be masked.<b>Copyright information:</b>Taken from "BatchPrimer3: A high throughput web application for PCR and sequencing primer design"http://www.biomedcentral.com/1471-2105/9/253BMC Bioinformatics 2008;9():253-253.Published online 29 May 2008PMCID:PMC2438325.

或者，可将无需保留的序列区域替换为"N"（）。可通过一对大括号"{}"指定需保留的序列区域，且仅能对一个需保留区域进行序列掩膜。<b>版权信息：</b>本文内容取自《BatchPrimer3：一款用于聚合酶链式反应（Polymerase Chain Reaction, PCR）与测序引物设计的高通量Web应用》，原文链接：http://www.biomedcentral.com/1471-2105/9/253，发表于《BMC生物信息学》2008年，9(): 253-253。该文于2008年5月29日在线发表，PMCID: PMC2438325。