3.內標（Internal Control
，IC）

內nei標biao是shi指zhi在zai同tong一yi反fan應ying管guan中zhong與yu靶ba序xu列lie共gong同tong擴kuo增zeng的de一yi段duan非fei靶ba序xu列lie分fen子zi。內nei標biao有you兩liang種zhong形xing式shi，一yi種zhong是shi使shi用yong天tian然ran樣yang品pin中zhong含han有you的de內nei參can基ji因yin作zuo為wei內nei標biao，另ling一yi種zhong是shi人ren工gong添tian加jia的de內nei標biao。內nei標biao的de最zui大da特te點dian是shi與yu靶ba序xu列lie共gong同tong擴kuo增zeng
，而er其qi他ta的de對dui照zhao都dou是shi獨du立li擴kuo增zeng。

3.1 內參基因

通常它們在各組織和細胞中的表達相對恒定
，在檢測基因的表達水平變化時常用它來做參照物。內參基因通常是持家基因（house-keeping gene）因為其表達水平受環境因素影響較小，而且在個體各個生長階段的幾乎全部組織中持續表達變化很小。常用的內參基因包括GAPDH、β-actin(BETA-actin)
、18sRNA
、B2M、HPRT和TBP等。

neicanjiyindeyoudianshiyuyangpinzhongdebajiyinjingliquanxiangtongdechulichengxu，keyijiankongcaiyang

，yunshu，hesuantiquhekuozengdequanbuguocheng。quedianshibutongwuzhong，butongshenglizhuangtaixia
，butongzuzhizhongdeneicanjiyincunzaiyidingdechayi。ruguoyangpinleixingshikouqiangye，yanshizidengyangpin，neicanjiyindelianghendikenengdaozhishiyanbuchengli。ruguojiancedeshihuanjingyangpinzeneicanjiyinkenengquanshixiao。

3.2人工內標

tianjiayizhongbuhuiganraobaxuliekuozengderengonghechengdeneibiao。xianzaiguowaidezhenduanshijihedabufendouhuijiangneibiaozhijietianjiazaifanyingyezhongyumobanyiqikuozeng
，danshizheyangdeneibiaobunengjiankongcaiyang，yunshuhehesuantiqudeguocheng。

haiyoulingyizhongxingshideneibiao

，shiyongrengonghechengdejiabingdu，zaihesuantiquqianzaimeiyifenyangpinzhongjiarudengliangdeneibiao
，zheyangjiukeyijiankongyangpindetiqudaokuozengdeguocheng。danshiyouyushirengongtianjiadaoyangpinzhong
，rengranbunengjiankongbaoneixijunbingdudeshifangqingkuang。