Prints’ Secrets

指紋形成機制

Fingerprints have been used to identify individuals for centuries. But now scientists may have figured out how these patterns are formed， according to a paper published in the journal Cell.

Previous studies have shown that fingerprints can be influenced by how fast the different layers of skin grow. Denis Headon at the University of Edinburgh， UK， and his colleagues started their study from a new perspective: how genes affect fingerprint patterns. They identified the genes related to limb development， which could serve as the groundwork for print formation， according to their work published in 2022.

However， many genes are not involved during this formation process. “The key is how they are deployed on the anatomy of the hand，” Headon told Nature， a science journal. The team studied the ridges on mouse toes and human cells grown artificially.

They found two kinds of elements work against each other. A protein called WNT， which is important in skin development， stimulates ridge formation. Another molecule， called BMP， inhibits the ridges. With the two elements “fighting” each other， they create the patterns of waves.

幾個世紀以來，人們一直用指紋識別不同的個體。發表在《細胞》雜志上的一篇論文表明，現在科學家們可能弄清楚了指紋形成的機制。

先前的研究表明，不同皮膚層生長的速度會影響指紋形成。英國愛丁堡大學的丹尼斯·赫頓和團隊成員從一個新的角度展開研究：基因是如何影響指紋圖案的。根據該研究團隊在2022年發表的研究成果，他們確定了人類肢體發育的相關基因，而這些基因可以成為指紋形成的基礎。

然而，許多基因并沒有參與指紋形成的過程。赫頓在接受科學雜志《自然》采訪時表示：“關鍵是這些基因如何作用于手的構造。”該研究團隊研習了老鼠腳趾上的脊，以及人工培養的人類細胞。

研究人員發現了兩種相互作用的元素。一種名為WNT的蛋白質在皮膚發育中很重要，能刺激脊狀凸起的形成，而另一種名為BMP的蛋白質會抑制脊狀凸起，產生凹槽。當這兩種元素相互“戰斗”時，就形成了波浪圖案。

The team also changed the timing and the location of the origins of the waves in simulations. They discovered that the waves collide in different ways， which helps to create the diversity of print patterns.

Interestingly， the analysis of the fingerprint patterns supported the Turing reaction-diffusion system. It was first proposed by UK scientist Alan Turing in 1952 to describe a self-organizing system that creates patterns in nature， such as the feather patterns in birds and stripes on zebra.

Based on the new study， it may be possible that the structures of human skin might be all generated by the same mechanism， Sarah Millar， a US biologist， told the website Science News. However， more studies on how the skin matures are needed to solve the mystery.

研究團隊還在模擬中改變了脊狀波形成的時間和位置，并發現脊狀波會以不同方式進行碰撞，這有助于形成不同的紋路圖案。

有趣的是，對指紋圖案的分析支持了“圖靈反應-擴散系統”。該機制最初由英國科學家艾倫·圖靈于1952年提出，用來描述諸如鳥類羽毛花紋、斑馬條紋等在自然界中形成圖案的自組織系統。

美國生物學家莎拉·米勒在接受科學新聞網站采訪時表示，根據這項新研究，人類皮膚的構造可能都是由相同機制形成。然而，要解開皮膚形成機制之謎，還需要進行更多有關皮膚如何發育成熟的研究。

Word Bank

collide /k?'la?d/ v. 碰撞；相撞

As he fell， his head collided with the table.