Daniel Fernandes preparing to take a sample.
© Adrian Daly
The standard creationist response to evidence that the human genome is not the perfectly designed blueprint we should expect from a flawless designer is to claim that ‘sin’ somehow caused it to become degraded. Discovery Institute fellow Michael J. Behe even introduced the biologically nonsensical notion of ‘genetic entropy’, which supposedly allows deleterious genes to spread throughout a species’ gene pool by some unexplained process — an idea that only those unfamiliar with how natural selection works could find convincing.
It is, of course, impossible for a genuinely deleterious gene to increase in frequency within a population unless it is linked to an advantageous trait whose benefits far outweigh its harmful effects. And if the genome were originally perfect, as Behe assumes, how could any advantageous mutation arise in the first place?
Behe, unwittingly or otherwise, appears to have abandoned any pretence that Intelligent Design is science rather than fundamentalist Christianity in a lab coat. By invoking an initial perfect creation followed by corruption through ‘sin’, he has simply retreated into theology — especially after his ‘irreducible complexity’ argument collapsed so spectacularly during the Kitzmiller v. Dover trial.
Even that feeble argument, however, has now fallen foul of evidence showing that deleterious variants and genetic disorders existed in the human genome long before the creationist narrative claims that ‘perfect’ humans were created somewhere in Mesopotamia just 6,000–10,000 years ago. A paper recently published in The New England Journal of Medicine by a team of researchers led by the University of Vienna and Liège University Hospital Centre reports the identification of genetic variants associated with a rare disorder in two prehistoric individuals who lived more than 12,000 years ago.
The individuals were discovered in 1963 at Grotta del Romito in southern Italy, buried in an embracing position. There was no sign of trauma. ‘Romito 1’, an adult female, was embracing ‘Romito 2’, an adolescent initially assumed to be male, whose reduced limb length suggested a height of about 110 cm (3 feet 7 inches). Palaeogenomic analysis, using DNA extracted from the petrous part of the temporal bone, has now shown that the adolescent was also female and was homozygous for a variant in the NPR2 gene, which is essential for normal bone growth. The two individuals were first-degree relatives, probably mother and daughter. The adult, Romito 1, was heterozygous for the same variant.
What this study makes clear is that genetic variants capable of causing disease were already present in the human genome thousands of years before the Bronze Age authors of Biblical origin myths imagined a special creation of ‘perfect’ humans without ancestry. These variants did not require some magical ingredient called ‘sin’ to arise — only the ordinary reality of imperfect replication and inheritance.
Why Do Deleterious Genes Persist in Populations? Creationists often assume that harmful mutations should be quickly eliminated, and therefore their presence must indicate some sort of post-creation “degeneration” or even a mystical force such as Behe’s imagined “genetic entropy”. In reality, evolutionary genetics has long explained why deleterious variants can persist in populations — and in some cases remain surprisingly common.Although the paper in The New England Journal of Medicine is behind an expensive paywall, the team’s findings are explained in a press release from the University of Vienna.
- Natural selection is not all-powerful
Natural selection does not remove every harmful mutation instantly. It only acts efficiently against variants that significantly reduce reproductive success. Many deleterious mutations have only mild effects, especially in modern environments, so selection against them is weak.
- Most harmful mutations are recessive
Many genetic disorders are caused by recessive variants, meaning they only produce disease when an individual inherits two copies. Carriers with only one copy are usually healthy, so the mutation can persist silently in the gene pool for many generations.
This is why disorders such as cystic fibrosis or Tay–Sachs can remain present even though the homozygous condition is harmful.
- Mutation is continual
Even if selection removes harmful variants, new mutations arise constantly. Every human child is born with dozens of new mutations not present in either parent. Evolution is therefore a balance between mutation introducing variation and selection removing the worst effects.
This is known as mutation–selection balance.
- Genetic drift can overwhelm selection
In small populations, chance plays a major role. A mildly harmful variant can become common simply through random inheritance, especially after population bottlenecks or founder events. Natural selection is not the only force shaping genomes.
- Some deleterious genes are linked to advantages
Occasionally, a mutation that is harmful in one context can be beneficial in another. The classic example is the sickle-cell variant: harmful in homozygotes, but protective against malaria in heterozygotes.
This is called balancing selection, and it shows that “bad” genes are not always purely bad.
- Effects depend on environment
A variant that is deleterious today may not have been harmful in the past, or may only cause problems under certain environmental conditions. Many diseases result from a mismatch between ancient genomes and modern lifestyles, not from “genetic decay”.
- Evolution produces workable, not perfect, genomes
Evolution does not design organisms from scratch. It works by modifying what already exists. As a result, genomes are full of compromises, trade-offs, and historical baggage — exactly what we would expect from a blind natural process, not from an all-knowing engineer.
In short: the persistence of deleterious variants is not mysterious, and it certainly does not require a theological concept like “sin”. It is an entirely predictable consequence of population genetics, imperfect replication, and evolutionary history.
Ancient DNA reveals 12,000-year-old case of rare genetic disease
Study reports the earliest genetic diagnosis in humans and provides new insight into rare diseases in prehistory
Researchers led by the University of Vienna and Liège University Hospital Centre have identified genetic variants associated with a rare inherited growth disorder in two prehistoric individuals who lived more than 12,000 years ago. Using ancient DNA analysis and modern clinical genetics, they diagnosed the condition in a mother and daughter buried together in southern Italy. Published in the New England Journal of Medicine, the study shows that paleogenomics can now reconstruct ancient population history and diagnose rare genetic diseases in prehistoric individuals.Summary
- Ancient DNA analysis revealed that two individuals buried together in southern Italy were closely related — most likely mother and daughter.
- In the younger individual, two altered copies of the NPR2 gene confirmed acromesomelic dysplasia (Maroteaux type), a condition marked by severe short stature and pronounced limb shortening; the older individual carried one altered copy linked to milder short stature.
- The findings show that rare genetic diseases were already present in prehistoric populations and can now be studied using paleogenomics.
- The younger individual's survival despite severe physical limitations suggests sustained care and social support within her community.
The discovery builds on a reanalysis of a well-known Upper Paleolithic burial discovered in 1963 at Grotta del Romito in southern Italy, which has long puzzled researchers. Unusual skeletal features and the circumstances of the burial raised longstanding questions about the relationship between the individuals and the medical reasons for their short stature.
A remarkable double burial raises questions
The two were interred together in an embrace. "Romito 2", an adolescent with pronounced limb shortening, previously assumed to be male, lay in the arms of "Romito 1", thought to be an adult female. No signs of trauma were observed. Romito 2 had an estimated height of about 110 cm, consistent with a rare skeletal growth disorder known as acromesomelic dysplasia, though this could not be confirmed solely from bones. Romito 1 was also shorter – about 145 cm –than average for the period. For decades, researchers debated their gender, relationship, and the possibility of a common cause of their short stature.
About the study
The team analysed ancient DNA extracted from the petrous part of the temporal bone of both individuals, a region known for preserving genetic material well. Genetic analysis established a first-degree relationship. The researchers then screened genes associated with skeletal growth and compared the identified variants with modern clinical data. This interdisciplinary approach, combining paleogenomics, clinical genetics, and physical anthropology, involved an international team from the University of Vienna and collaborators in Italy, Portugal, and Belgium.
Earliest genetic diagnosis in humans
The analysis showed that both individuals were female and first-degree relatives, most likely a mother and daughter. In Romito 2, researchers identified a homozygous variant in the NPR2 gene, which is essential for bone growth. This confirmed a diagnosis of acromesomelic dysplasia, Maroteaux type — a very rare inherited disorder characterized by severe short stature and marked shortening of the limbs. Genetic data from Romito 1 indicate that she carried one altered copy of the same gene, a condition associated with milder short stature.
Rare diseases in human history
By applying ancient DNA analysis, we can now identify specific mutations in prehistoric individuals. This helps establish how far back rare genetic conditions existed and may also uncover previously unknown variants.
Dr. Ron Pinhasi, co-lead author
University of Vienna.Identifying both individuals as female and closely related turns this burial into a familial genetic case. The older woman's milder short stature likely reflects a heterozygous mutation, showing how the same gene affected members of a prehistoric family differently.
Daniel Fernandes, first author
University of Coimbra
Coimbra, Portugal.
Clinically, the results highlight the deep history of rare diseases.
Rare genetic diseases are not a modern phenomenon but have been present throughout human history. Understanding their history may help recognising such conditions today.
Adrian Daly, co-lead author
Liège University Hospital Centre.
Evidence of social care
Despite severe physical limitations, Romito 2 survived into adolescence or adulthood, suggesting sustained care within her community.
We believe her survival would have required sustained support from her group, including help with food and mobility in a challenging environment.
Adrian Daly.
Publication:
What this study from Grotta del Romito demonstrates is that the human genome has never been a pristine, flawless “design” subsequently corrupted by some mystical force called sin. Genetic variants capable of causing serious disorders were already present in human populations more than 12,000 years ago, long before the Bronze Age authors of Biblical mythology imagined their tale of special creation in Mesopotamia.
Far from being evidence of a fallen perfection, these findings are exactly what evolutionary biology predicts. Mutations arise naturally through imperfect replication, and population genetics explains perfectly well why even harmful variants can persist for thousands of years. There is no need for supernatural degradation, only the ordinary workings of inheritance, chance, and selection in real populations over deep time.
Once again, the fossil record, archaeology, and now palaeogenomics all tell the same consistent story: humanity has a long evolutionary history, complete with the genetic variation — beneficial, neutral, and occasionally harmful — that inevitably accompanies it. The idea of an original “perfect genome” is not science, but theology dressed up in scientific language, and it collapses as soon as evidence from the real world is allowed to speak.
Creationism, as always, is left trying to explain away the data, while evolution simply explains it.
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