Laurence A Moran - new book on junk DNA

I was reading the Pharyngula blog which mentioned that Larry Moran has a new book on junk DNA - some info here
Any thoughts on the likely quality of the work in this book by those familiar with his work? I am reading something on evo-devo at the moment and some other things, but want to line up my next read

He has posted many excerpts and summaries on his blog.

@Joe_Felsenstein is listed as a reviewer, so may be able to give more info.

We can await reviews. But Larry is a fine biochemist and educator with strong opinions about junk DNA, and I happen to agree with him on his views. There is unfortunately a lot of belief out there, even among scientists who should know better, that much of this DNA has hidden functionality. This was terribly popularized by the ENCODE project some years ago, and we still see views like that being propagated. So I give away my bias. Larry is “fighting the good fight”, in my view, but I hope that the book is good and that it is fairly reviewed (as in not reviewed by a bunch of ENCODIANS).


I expect it to be as good as science-writing intended for both a lay audience and professionals can get because there will be no dumbing things down.

1 Like

Larry is a highly competent scientist and this is his area of expertise. So I would expect the work to be of high quality. I haven’t read the book but I expect it to be more detailed explanations of things he has regularly discussed on his blog. So should be a good read.


It’s been well reviewed, including by some familar names:

What’s in Your Genome? is a thought-provoking and pugnacious book that will make you wonder afresh at the molecular intricacies of life. When it comes to our genomes, we humans are nothing special – Moran makes a convincing argument that the vast majority of our sloppy human genome is not mysterious genetic treasures but boring old junk.”

Kat Arney, science writer, broadcaster, and author of Rebel Cell: Cancer, Evolution, and the New Science of Life’s Oldest Betrayal

What’s in Your Genome? is an enormously useful book and a powerful and necessary defense of the concept of junk DNA. Moran presents a clear summary of how the public can be misled by even the most experienced of science writers. We need more outspoken scientists like him.”

W. Ford Doolittle, Professor Emeritus, Department of Biochemistry and Molecular Biology, Dalhousie University

“Recently most molecular biologists and genomicists have been convinced that most of the sequence in our genomes is intricately functional, that the idea of junk DNA was a mistake that can now be mostly discarded. But almost all researchers in molecular evolution have disagreed with this. Laurence A. Moran’s clear and incisive book explains why many biologists are so thoroughly mistaken – why our genomes are ‘messy,’ and full of junk DNA.”

@Joe_Felsenstein, Professor Emeritus, Departments of Genome Sciences and of Biology, University of Washington, Seattle

“The writing is so crisp and exquisite that it’s almost as if a magical code is being revealed whereby the reader is being invited to step inside a furious scientific debate.”

Lee McIntyre, Research Fellow, Center for Philosophy and History of Science, Boston University

“A serious warning to scientists and science writers who, to seduce their public, privilege the too-fast announcement of novelties and revolutions instead of doing a cautious examination of the results. Laurence A. Moran has written a deeply honest and extremely well-documented book on one of the hottest recent controversies in science. A master class on what science is and what it must continue to be.”

Michel Morange, Professor Emeritus of Biology, Institute of the History and Philosophy of Sciences and Techniques , Université Paris 1 Panthéon-Sorbonne

“Laurence A. Moran lucidly explains the science behind an ugly yet thrilling truth – the DNA sequences that specify our body’s proteins and RNAs are indeed finely honed by natural selection (like a Swiss watch), but they are only tiny islands of information embedded in a swamp of evolved gibberish.”

Rosemary J. Redfield, Professor Emerita of Zoology, University of British Columbia

“Rarely does a science writer respect their audience enough to bring them into the weeds of confusion the way that Dr. Moran does, but the rewards are there to be reaped. A thorough reader will never look at the genome of any living organism or the concept of junk DNA the same way after reading this and will be left wondering how so many baseless claims have made headlines in recent years. In the capable hands of Dr. Moran, we can all learn to untangle facts from unsupported assertions and come away understanding why our genome is structured in precisely the way that it is.”

Ethan Siegel, Theoretical Astrophysicist and founder of Starts With A Bang

“Junk DNA is a concept that’s not well understood, even by most biologists, yet arguments about its existence are commonplace. In What’s in Your Genome?, Moran brings together evolution, genomics, and decades of scientific history to make the case for it. Even if you don’t agree with all of his conclusions, you’d benefit from the clarity he brings to the topic.”

John R. Timmer, Science Editor, Ars Technica

“This book is a clear and fascinating guide to the exotic menagerie of elements that exists in our DNA and a no-holds-barred defense of an important but often ignored fact about the human genome: most of it has no function. But Moran shows that, even without function, junk DNA is incredibly interesting.”

Michael White, Associate Professor of Genetics, Washington University in St. Louis School of Medicine


Book bought. Who knows, I might even understand some of it, somewhere, somehow.

I’ve ordered the book but it hasn’t arrived yet, so what I have to say is based on Larry’s posting on the subject on Sandwalk over the years and on reading his biochem textbook. And, I guess, on various conversations at meetings. Based on all that, Larry knows what he’s talking about and would certainly be a better source than, say, anyone involved with ENCODE or the average molecular biologist.


Thanks all - good to have feedback from those familiar with him / his work.

Yep - I have been looking at those. Definitely makes me want to buy the book, just wanted to check on whether he was fringe in his views.

One of the problems of not being in the field or even really reading much in it is not knowing who these people are and how much weight to put on their opinions. When you say by familiar names, do you mean people that are well known in the field or do you mean it in some other way?

Well if you agree with him, then I definitely have to get it :stuck_out_tongue_winking_eye:

1 Like

It would likely be of very high quality. If you are under the false impression that noncoding=junk, it would be worth a read.

The familiar names I was referring to were W. Ford Doolittle and Joe Felsenstein, both of whom are well known in the field, and also Joe because he’s present here on PS! @Joe_Felsenstein

I bought it on kindle so will be reading over the next week or so. I will leave any musings about it to you if you are of a mind to share thoughts when you do read it.

This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.

I came across Moran’s discussion of the onion test on page 39 of the kindle version (I assume the page numbers match the print)

Ryan Gregory has created the Onion Test as a way of checking to see if you have an explanation of genome size variation that’s better than junk DNA. Gregory points out that the onion Alium cepa has a 16 Gb genome that’s 5 times larger than ours. Related species of onion have genomes that range from about 7 Gb to 30 Gb. Here’s how he described the Onion Test on his blog in 2007: The onion test is a simple reality check for anyone who thinks they have come up with a universal function for junk DNA. Whatever your proposed function, ask yourself this question: Can I explain why an onion needs about five times more noncoding DNA than a human?

I decided to ask Chat GPT what the onion test is

The term “onion test” is associated with discussions about “junk DNA” in genetics and genomics. Junk DNA refers to the non-coding regions of the genome that do not appear to encode functional genes or have a known function.

The onion test is a metaphor used to challenge the notion that certain DNA sequences are functionally insignificant or “junk.” It is based on the observation that the genomes of complex organisms like humans contain a much larger amount of DNA than simpler organisms like onions, despite having a comparable number of genes. The argument is that if a significant portion of the genome is truly non-functional or junk, then organisms with larger genomes would have more complexity or advanced features compared to those with smaller genomes.

In other words, the onion test questions the assumption that the extra non-coding DNA in complex organisms lacks any functional significance. It suggests that this additional DNA may have important roles that are not yet fully understood or appreciated. Scientists are actively researching and investigating the functions and evolutionary significance of non-coding DNA, and the onion test serves as a reminder that our understanding of the genome is still evolving.

So… do I believe the words of the person who came up with the onion test (as cited by Moran), or AI instead? I was prompted to ask it after reading about Moran’s complaints about its output on Junk DNA in general

1 Like

I should probably note that my question above was meant tongue in cheek. Really enjoying the book - massively stretching my understanding so lots to follow up with.
Who knew i would get excited about retrotransposons


I’m not sure why anyone asks ChatGPT anything, except for laughs. Yes, ChatGPT is confused here, if an unconscious thing can be confused. Rule of thumb: if Larry Moran says one thing and ChatGPT says another, trust Larry. Further rule: never ask ChatGPT a question when you are genuinely interested in the answer.


Personally, I prefer the bladderwort test.

The gene count is comparable to other plant genomes, but the bladderwort genome is a tiny fraction of the size at just 0.082 Gbp. Compare that to the 3 Gbp of the human genome, or the much larger onion genome. The bladderwort has lost almost all of its junk DNA, and it’s doing just fine.


Different sort of test. The onion test doesn’t compare an onion genome to a human genome. It compares the genomes of two species of onion, one of which is twice the size of the other one. It asks why two species with nearly identical phenotypes need such radically different amounts of DNA. Hey, maybe a lot of it is junk.