最近在复习HGVS命名，当做个人翻译笔记吧。
HGVS，全称是Human Genome Variation Society，人类基因组变异协会的缩写。
本周翻译的是第二部分Substitution，原文地址http://varnomen.hgvs.org/recommendations/DNA/variant/substitution/
【替换/点突变】Substitution
定义：与参考序列相比，一个核苷酸被另一个核苷酸替换
格式：前缀（所使用的参考序列）+ . +取代位置+参考核苷酸>新核苷酸，举例：g.123A>G
要点：
①接受的参考序列包括g. m. c. n.
②涉及2个及以上连续的核苷酸改变时，优先描述为缺失/插入
③经过检测，发现核苷酸未改变，描述为c.123A=，g.4567T=
④描述c.76_77delinsTT优先于c.[76A>T;77G>T]，注意，依据定义，该突变不能描述为替换（类似于c.76_77AG>TT or c.76AG>TT）
⑤多态性不能描述为c.76A/G（应该描述为NM_004006.1:c.76A>G）
举例：
NC_000023.10:g.33038255C>A
a substitution of the C nucleotide at g.33038255 for an A
NG_012232.1(NM_004006.1):c.93+1G>T
a substitution of the G nucleotide at c.93+1 (coding DNA reference sequence) with a T
LRG_199t1:c.79_80delinsTT or c.[79G>T;80C>T]
the description c.79_80delinsTT is preferred over c.[79G>T;80C>T], unless either of the two variants (79G>T or c.80C>T) is known as a frequently occurring variant.
注意事项: based on the definition of a substitution, i.e. one nucleotide replaced by one other nucleotide, this change can not be described as a substitution like c.79_80GC>TT or c.79GC>TT
描述c.79_80delinsTT优先于c.[79G>T;80C>T]
NM_004006.1:c.[145C>T;147C>G]
two substitutions replacing codon CGC (position c.145 to c.147) with TGG
注意事项: the variant can also be described as NM_004006.1:c.145_147delinsTGG, i.e. a deletion/insertion. The deletion/insertion format is preferred unless either of the two variants (c.145C>T or c.147C>G) is known as a frequently occurring variant.
描述c.145_147delinsTGG优先于c.[145C>T;147C>G]
LRG_199t1:c.54G>H
a substitution of the G nucleotide at c.54 (coding DNA reference sequence) with a A, C or T (IUPAC code “H”, see Standards)
命名遵循核酸序列中“不完全指定碱基”的命名（Adenine腺嘌呤A，Cytosine胞嘧啶C，Guanine鸟嘌呤G，Thymine胸腺嘧啶T）
NM_004006.1:c.123=
a screen was performed showing that nucleotide c.123 was a “C” as in the coding DNA reference sequence (the nucleotide was not changed). Alternative NM_004006.1:c.123C=.
LRG_199t1:c.85=/T>C
a mosaic case where at position 85 besides the normal sequence (a T, described as “=”) also chromosomes are found containing a C (c.85T>C)
同源嵌合体，样本是c.85＝和c.85T>C的混合体
NM_004006.1:c.85=//T>C
a chimeric case, i.e. the sample is a mix of cells containing c.85= and c.85T>C.
异源嵌合体，样本是c.85＝和c.85T>C的混合体
