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Feature Key           GC_signal

Definition            GC框；一段保守的富含GC的区域，定位在真核转录单位起始位点的上游，可以位于原点或有多个拷贝。一致序列=GGGCGG

Optional qualifiers   /citation=[number]
                      /db_xref="<database>:<identifier>"                     
                      /evidence=<evidence_value>
                      /gene="text"
                      /label=feature_label
                      /map="text"
                      /note="text"
                      /partial
                      /usedin=accnum:feature_label

Organism scope        Eukaryotes and eukaryotic viruses

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Feature Key           gene

Definition           在生物学上一定有意义和价值的序列定义为基因，并命名。

Optional qualifiers   /allele="text"
                      /citation=[number]
                      /db_xref="<database>:<identifier>"
                      /evidence=<evidence_value>
                      /function="text"
                      /label=feature_label
                      /map="text"
                      /note="text"
                      /partial
                      /product="text"
                      /pseudo
                      /phenotype="text"
                      /standard_name="text"
                      /usedin=accnum:feature_label
       

Comment              gene这个字段描述相对应于一个遗传特征或表型的DNA序列，定义上并不严格限定它的两端位置。它是代表了基因所在的位置

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Feature Key           iDNA

Definition             干预DNA；着DNA可通过几种重组方式被去除。

Optional qualifiers   /citation=[number]
                      /db_xref="<database>:<identifier>"                     
                      /evidence=<evidence_value>
                      /function="text"
                      /label=feature_label
                      /gene="text"
                      /map="text"
                      /note="text"
                      /number=unquoted text (single token)
                      /partial
                      /standard_name="text"
                      /usedin=accnum:feature_label

Molecule scope        DNA

Comment               例如免疫球蛋白基因的内部加工过程中

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Feature Key           intron

Definition            一段DNA序列，在转录的过程中通过剪切机制被去除，使其两端的外显子连在一起

Optional qualifiers   /citation=[number]
                      /cons_splice=(5'site:<bool>,3'site:<bool>)
                      /db_xref="<database>:<identifier>"                     
                      /evidence=<evidence_value>
                      /function="text"
                      /gene="text"
                      /label=feature_label
                      /map="text"
                      /note="text"
                      /number=unquoted text (single token)
                      /partial
                      /standard_name="text"
                      /usedin=accnum:feature_label

Comment               cons_splice只是当其中一个内含子的剪切位点不符合GT...AG的一致序列时使用

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Feature Key           J_segment
 

Definition            免疫球蛋白轻链和重链以及T细胞受体α、β、γ链的添加片段

Optional qualifiers   /citation=[number]
                      /db_xref="<database>:<identifier>"
                      /evidence=<evidence_value>
                      /gene="text"
                      /map="text"
                      /note="text"
                      /partial
                      /product="text"
                      /pseudo
                      /standard_name="text"
                      /usedin=accnum:feature_label