Genetic Clues from the Flood Account

"Like in the Creation story, there are only a few verses in the Flood account that help us with our model. 

---About 10 generations after Creation, a severe, short bottleneck occurred in the human population. From untold numbers of people, the entire world population was reduced to eight souls with only three reproducing couples.

“So Noah, with his sons, his wife, and his sons’ wives, went into the ark because of the waters of the flood.” Gen 7:7

“Now the sons of Noah who went out of the ark were Shem, Ham, and Japheth… These three were the sons of Noah, and from these the whole earth was populated.” Gen 9:18–19

We can draw many important deductions from these statements. 

Q: For instance, based on Genesis 7 and 9, how many Y

chromosomes were on the Ark? 

A: The answer: one. Yes, there were four men, but Noah gave his Y chromosome to each of his sons. Unless there was a mutation (entirely possible), each of the sons carried the exact same Y chromosome. 

*We do not know how much mutation occurred prior to the flood. With the long life spans of the antediluvian patriarchs, it may be reasonable to assume little mutation had taken place, but all of Creation, including the human genome, had been cursed, so it may not be wise to conclude that there was no mutation prior to the Flood. The amount of mutation may be a moot point, however, for, if it occurred, the Flood should have wiped out most traces of it (all of it in the case of the Y chromosome).

 

Q: How many mitochondrial DNA lineages were on the Ark? 

A: The answer: three. Yes, there were four women, but the Bible does not record Noah’s wife as having any children after the Flood (in this case, girl children). And notice the claim in Gen 9:19, “These three were the sons of Noah, and from these the whole earth was populated.” This is a strong indication that Noah’s wife did not contribute anything else to the world’s population. 

With no prohibition against sibling marriage, yet, one or more of the daughters-in-law may have been her daughter, but this does not change the fact that, at first glance, we expect a maximum of three mitochondrial lineages in the current world population. There is a chance that there will be less, if there was very little mutation before the Flood or if several of the daughters-in-law were closely related. At most, we do not expect more than four.

 

Q: How many X chromosome lineages were on the Ark? 

A: That depends. If you count it all up, you get eight. If, by chance, Noah’s wife passed on the same X chromosome to each of her three sons (25% probability), then there were seven. If Noah had a daughter after the Flood (not expected, but possible), there could be as many as nine X chromosome lineages. Either way, this is a considerable amount of genetic material. 

And since X chromosomes recombine (in females), we are potentially looking at a huge amount of genetic diversity within the X chromosomes of the world.

Q: Does this fit the evidence? 

A: Absolutely! 

 

---It turns out that Y chromosomes are similar worldwide. According to the evolutionists, no “ancient” (i.e., highly mutated or highly divergent) Y chromosomes have been found. 

This serves as a bit of a puzzle to the evolutionist, and they have had to resort to calling for a higher “reproductive variance” among men than women, high rates of “gene conversion” in the Y chromosome, or perhaps a “selective sweep” that wiped out the other male lines.

 

*As it turns out, there are three main mitochondrial DNA lineages

found across the world. The evolutionists have labeled these lines “M”, “N”, and “R”, so we’ll refer to them by the same names. They would not say these came off the Ark. They claim they were derived from older lines found in Africa, but this is based on a suite of assumptions 

It also turns out that M, N, and R differ by only a few mutations. This gives us some indication of the amount of mutation that occurred in the generations prior to the Flood.

Let’s assume ten female generations from Eve to the ladies on the Ark. M and N are separated by about 8 mutations (a small fraction of the 16,500 letters in the mitochondrial genome). R is only 1 mutation away from N. This is an indication of the mutational load that occurred before the Flood. Given the assumption that mutations occur at equal rates in all lines, about four mutations separate M and N each from Eve (maybe four mutations in each line in ten generations). But what about R? It is very similar to N. 

Q: Were N and R sisters, or perhaps more closely related to each other than they were to M? 

---We’ll never know, but it sure is fascinating to think about.

 

One more line of evidence crops up in the amount of genetic diversity that has been found within people worldwide. 

*Essentially, much less has been found than most (i.e., evolutionists!) predicted. 

The general lack of diversity among people is the reason the Out of Africa model has humanity going through a disastrous, near-extinction bottleneck with only about 10,000 (and perhaps as few as 1,000) people surviving.

 

-*-However, the reason for this lack of diversity is twofold. 

First, the human race started out with only two people. 

Second, the human race is not that old and has not accumulated a lot of mutations, despite the high mutation rate. 

Third, there actually was a bottleneck event, Noah’s Flood!""

 CMI