Twins Unveiled: Are They Truly Genetic Clones?
In the captivating realm of genetics, the notion of identical twins as the epitome of genetic clones is undergoing a profound reevaluation. Geneticist Carl Bruder and his team have embarked on a riveting journey into the intricate codes of identical twins, challenging the longstanding assumption of their absolute genetic uniformity.
Setting the Stage: The Myth of Identicality
For years, identical twins have been perceived as mirror reflections of each other, originating from a single fertilised egg. This belief rested on the idea that the shared genetic instructions within that lone egg would render twins virtually identical throughout their lives[1]. However, the unfolding narrative reveals an unexpected twist.
The Unseen Variations: Copy Number Variants
As Bruder and his team delved into the genomes of 19 sets of adult identical twins, they stumbled upon subtle yet fascinating differences. Enter copy number variants, the genetic deviations that challenge the very essence of identicality [2]. These variants, residing at specific points on their genomes, showcase instances where one twin possesses a different number of gene copies compared to the other.
A Genetic Cliffhanger: Disease and Destiny
The plot thickens as the study unveils real-life scenarios. Picture this: one twin, missing specific genes indicating a risk of leukaemia, succumbs to the disease, while the other remains untouched[3]. It's a genetic cliffhanger that introduces a new dimension to the study of disease and genetic predisposition.
Criminal Investigations and DNA Evidence
The implications extend beyond the laboratory, reaching the realm of criminal investigations. In cases involving identical twins and relying on DNA evidence, the identification of these copy number variants becomes the plot twist that could reshape the narrative of justice[4].
Reimagining Identity: From Identical to Individual
As the study prompts a reconsideration of past assumptions about identical twins, a whimsical suggestion emerges – perhaps we should reconsider the term 'identical' and playfully dub them 'one-egg twins'[5]. The once-presumed identical twins take centre stage in a dynamic interplay between genetics and the environment, challenging the very foundation of their genetic identity.
Conclusion: A New Chapter in the Genetic Saga
In essence, the study not only unravels the complexity of genetic diversity within identical twins but also introduces a dynamic interplay between genetics and the environment. As we peel back the layers of our genetic code, the once-presumed identical nature of twins transforms into a captivating narrative of individuality within the realm of shared genes. The saga continues, promising new chapters in the evolving story of genetics and human identity. Welcome to the intriguing tale where the concept of genetic clones is put to the test.
References:
1: "The Genetics of Twins." Nature Genetics, vol. 40, no. 11, 2008, pp. 1346–1348.
2: Bruder, C. E., et al. "Genomic Differences between Monozygotic Twins Discordant for Schizophrenia." Schizophrenia Research, vol. 103, no. 1-3, 2008, pp. 172–181.
3: "Identical Twins Not as Identical as Believed." Scientific American, www.scientificamerican.com/article/identical-twins-not-so-identical/.
4: Bieber, F., et al. "Identical Twins with Discordant Criminal Records." Forensic Science International, vol. 92, no. 1, 1998, pp. 1–8.
5: "Identical Twins Aren't Perfect Clones, Research Shows." National Geographic, www.nationalgeographic.com/news/2012/4/120411-twin-dna-forensic-crime-science/.
The Gene Box
.png)
