AISSU两位“小小科学家”探索神奇的DNA世界

天文学家卡尔•萨根曾经说过：“每个人在他们幼年的时候都是科学家，因为每个孩子都和科学家一样，对自然界的奇观满怀着好奇和敬畏。”

深大师院国际高中致力于向不同层次的学生提供各种机会，鼓励学生独立思考、不断探索，注重培养学生的国际视野、前沿意识和人文素养，旨在将学生培养为全面发展、英语特长的国际人才。

这个寒假，AS年级陈本铨（左）、余鸿宽（右）两位同学在学校的大力推荐下，带着对生物科学的好奇和不可遏止的求知欲望，参加中信银行联合生物行业龙头企业华大基因共同打造的超高含金量背景提升项目——未来生物学家之基因探秘。

在专业指导老师的带领下，他们探秘我国首个获批筹建的基因库，学习生命遗传物质DNA的各种知识，利用顶级实验室设备进行“如何用基因测序鉴定物种”、“DNA指纹图谱与司法侦查”、“亲手操作转基因”、“运动基因揭秘”四大经典基因实验项目……极大地开拓了科学视野，锻炼了科学思维。

他们尽情在生物学的海洋里徜徉，大口吮吸着新鲜的生物知识，利用这6天学到的知识以及收集到的文献资料，并结合自己的想法，分析科学话题，畅谈基因知识。

凭借积极的态度和突出的表现，陈本铨、余鸿宽两位同学均拿下“优秀学员”的荣誉称号！

陈本铨、余鸿宽获“优秀学员”

AISSU老师到场支持虽然项目只有短短6天，但两位同学均表示受益良多。

在这里，他们也将分享自己的感受。

AS-4 余鸿宽我很荣幸能代表学校参加此次活动，这次活动对我来说意义非凡。

首先，这是一个非常有含金量的实操性活动。

华大学院的实验室里有很多非常先进的仪器设备，在老师的指导下，我完成了许多相对复杂和高要求的实验。

例如，华大学院的实验室里配备有非常精确的移液枪，这也是我第一次亲眼见到并亲手操纵这种仪器。

在做实验的时候我就可以提取到以微升为单位的液体，这样既增加了实验的精确性，又不用浪费太多材料。

这么多实验中，令我印象最深刻的实验是DNA条形码实验。

这个实验的原理就是在鱼肉细胞的线粒体中，有一个DNA序列叫做CO1，每种鱼的CO1序列都是不同的，通过检测这个序列并拿到数据库去比对，我们就能很清楚地知道这个鱼的品种了。

我们先切了一小块鱼肉，之后加入裂解液裂解细胞；加入裂解液后利用离心的方法，鱼肉细胞里的油会浮在最上层；利用移液枪将油抽出后，加入无水乙醇去溶解除DNA以外的杂质；

之后向试管里加入硅去吸附DNA，并把无水乙醇滤走；往硅固体里加入水，DNA便会融在水里，把硅过滤掉就得到了只含有DNA片段的溶液，经过

扩增后就可以拿去数据库比对了。

其次，华大学院的老师们都有渊博的学识。

在带领我们做实验的同时，又不断地给我们复习和巩固已经学过的知识，此外还普及了一些非常前沿的知识，这让我们开拓了视野。

我记得最清楚的就是华大的老师们向我们介绍第二代DNA测序仪的工作原理，让我们了解到科技的发达让DNA测序变得快捷和准确。

对于我来说，经过这次活动后，我对生物信息学萌生了兴趣，因为这门学科是计算机科学和生物学的交叉，或许不久的将来我将会申请这个major。

我推荐对生物感兴趣和选了生物课的同学有机会的话参加这个活动，因为这个活动做的所有实验都是和A-Level生物对标的，在巩固知识的同时又能接触很多前沿的生物方面的东西，这无疑是非常有价值的。

最后，我想表达一下我的感激之情。

感谢学校老师的认可和支持，推荐我去这样一个高水平的活动，让我有机会和其他优秀的学生一起竞争、学习；感谢我的父母，感谢他们能理解并允许我在开学后参加活动；

感谢中信银行的李老师，是她每天陪着我们一起去华大学院，并且在午餐上对我们多加照顾；感谢华大基因的各位老师们，是你们教会了我许多前沿的知识和

实验的规范，这将会对我今后的学习产生有利的影响。

AS-1 陈本铨

It is widely held among biology teachers and the scientific community that fieldwork is valuable, but little is heard about students' perception of fieldwork or about the reasons for their liking or disliking fieldwork.

However, right after the spring festival, a special team comprising of eight high-school students who aspire to make our contributions in the future field of biology met at the BGI headquarters under the guidance of a responsible teacher from the CITIC Bank.

On the first day, eight future biologists went to the National Genome Library where we started a journey of exploration in bioscience and gene technology.

 At this databank ,cutting-edge scientific equipment and rich examples of animals and plants really blow our minds.

Then for the rest of the journey, we stayed at the laboratory, learned about lab safety instructions and  conducted a series of biological experiments ,including DNA barcoding and fish DNA extraction, Forensic detection and DNA fingerprinting, analyzing our athletic genes and PCR technique and so on.

Among theses marvellous experiments , the one I fancy the most is the human ACTN3 gene and PCR simply because it tells me which type of muscle fibres I have, slow twitch(Type 1) muscle fibers or fast twitch(Type 2) muscle fibers.

First of all, we collected our DNA via saliva and added a host of different agents(i.e.lysis buffers, binding buffers and proteinases) into it to extract our DNA.

Then we have them undergone PCR reactions in thermal cylcers and finally used gel electrophoresis and a UV imaging system to see which type we belong to.

Unsurprisingly, I find myself to be RX type, a balance reached between type 1 and 2 muscle fibres.

On the final day, we gave our presentations in the form of two members in a group, and my group was assigned the topic of gene editing.

In the preparations for this topic, I looked into the goals, methods and applications of editing genes.

My partner Luna and I talked about the latest and most advanced tool called CRISPR, or more correctly CRISPR-CAS9 which is, undoubtedly, changing the entire field of biology.

It was originally described as an immune system in bacteria and archea against the invasion of virus, which was probably the oldest war waged on the earth.

Basically, this immune response is all about the protein-RNA duo.

When some of bacteria get infected by a virus, they save a chunk of its genome in a long string-like DNA called crispr locus and they use each chunk of DNA as a template to synthesize a similar molecule called RNA.

 Here, this protein acts as a guide to find the matching DNA and Cas9 is simply a nuclease cutting wherever its boss, guide RNA, tells it to.

So the next time ,this virus shows up ,the guide RNA find the matching chunk of DNA and calls over Cas9 to chop it up and destroy it.

To summarise, this unique experience at BGI lab with all these patient and knowledgeable mentors successfully overthrew how I perceive the subject biology and again taught us the vital importance of cooperation and teamwork.

Finally, just like what BGI says and does all the time, their aspiration as well as ours now is to use genomics to benefit the human race in the future.