23andMe: Got Genome Analyzed?

“For as little as $1,000 and a saliva sample, customers will be able to learn what is known so far about how the billions of bits in their biological code shape who they are,” mentions Amy Harmon.

23andMe is one of the start up companies that gives you a full report of your genome (23 DNA) for a low cost. You can find out whether you are genetically susceptible to a disease; you can also check whether there is a reason why you like brussel sprouts. This new concept of DNA exploration, like any other scientific innovations, is quite controversial. What if you find out something bad in your DNA? What if the insurance companies find out about your bad genes? What about the good genes?

Yes there are many aspects of DNA exploration that need to be tightly regulated. But there are very positive information one can find from them as well. What if you found out you are susceptible to diabetes, would you still crave for those candy bars? How about heart attack, won’t you hit the gym? I mean you can use the info to change your life and to live longer.

Wait…that is not the end of the story….rumor has it that there is a connection between Google and 23andMe…and that is not bad. I can only imagine when I will be able to Google any gene of mine to compare it with that of others. If companies like Google  and 23andMe join hands, that can be great for researchers as well. Science, every time it introduces a new concept has always been ridiculed. Tommy Lee Jones says in Men in Black, “1500 years ago people knew the world was flat, 500 years ago people knew the Earth was the center of the Universe and 15 minutes ago,…….” Well, “15 minutes ago you knew you were never going to have a heart attack but now you do so get your butt to the gym and exercise!” thats what these new companies can tell us.

Human Inbreeding: A better understanding

Unions contracted between persons biologically related as second cousins or closer (F ≥ 0.0156) are categorized as consanguineous. It is very confusing whether children of consanguineous marriages are genetically predisposed to any developmental defects. In my previous article ‘Human Inbreeding: What are the consequences?’ I tried to explain the deleterious effects inbreeding may cause. The articles I read at that time were not very conclusive whether inbreeding is beneficial or deleterious. So, I decided to dig up some more scientific journals to find out the effects of inbreeding.

One article I found, reasserted the former argument that inbreeding does not have any effect on fertility (spontaneous abortions and stillbirths) of women. However, higher rates of neonatal and post-neonatal deaths, and deaths of children younger than 5 years were observed in consanguineous couples. I then thought, does inbreeding affect the fertility of men? A study involving Middle-Eastern Males demonstrated that consanguinity and the familial clustering increased the chances of having infertility problems 2.6 times higher in cases than controls. So, I am thinking even though inbreeding does not cause any aberrant pregnancies, inbreeding does have adverse effects on male fertility and on survival of newborn children.

I have also wondered whether inbreeding plays a role in other diseases. While searching for answers to satisfy my curiosity, I found that researchers who have looked at Middle East and North Africa region have pointed out that in the Islamic Arabs residing in these regions, there is a high prevalence of first-cousin consanguinity. Hemoglobin disorders, inherited metabolic disorders, neurogenetic disorders, and birth defects are also relatively common in this part of the world. One can thus ask a question that may be these diseases can be credited to, at least in part to the inbreeding?

Also, medical professionals have found “significant association between parental consanguinity and congenital hypothyroidism.” Congenital hypothyroidism seems to correlate with the degree of consanguinity—children of first cousins are more prone to than those of second cousins.

Amid all the confusions, it is very well accepted that among genetic disorders, only autosomal recessive disorders are strongly associated with consanguinity. However, there are ample of studies showing that in a population with a high rate of consanguinity, there is a significant increase in the prevalence of common adult diseases like mental disorders, heart diseases, gastro-intestinal disorders, hypertension, hearing deficit, and cancer. Interestingly though, a study in Arab populations, however demonstrated that reduction of overall cancer risk was associated with increased coefficient of inbreeding (F). Both older and younger healthy men had significantly higher F but only women over 30 years of age with higher F had reduction of overall cancer risk. This study showed that being more inbred was associated with a reduction in overall cancer risk by about 25%.

I am not sure what to make of the relationship between inbreeding and cancer but I am certain that in breeding may have adverse affects in humans and it should not be encouraged.

More readings
Examples of inbreeding in humans
Probability of inbreeding

References:

Kobeissi and Inhorn; Health issues in the Arab American community. Male infertility in Lebanon: a case-controlled study.
Kerkeni et. al.; Interplay of socio-economic factors, consanguinity, fertility, and offspring mortality in Monastir, Tunisia.
Saadallah and Rashed; Newborn screening: experiences in the Middle East and North Africa.
Hashemipour, et. al.; Parental consanguinity among parents of neonates with congenital hypothyroidism in Isfahan.
Hamamy, et. al.; Consanguinity and genetic disorders. Profile from Jordan.
Bener, et. al.; Consanguineous marriages and their effects on common adult diseases: studies from an endogamous population.
Denic et. al.; Risk of cancer in an inbred population.

Who killed the dinosaurs?

There are the followers of Gerald L.K Smith, the father of theological theme parks who believed that the world was created by God a mere 6,000 years ago where dinosaurs and humans co-existed in the beginning. Then there are those of us who believe in evolution. We read the disclaimer that the Flintstones is just a cartoon and not a depiction of a young earth! Laugh Out Loud.

It is probably a coincidence that I was reading about Mr. Smith and the next thing I read was Time’s article suggesting that the Deccan Traps of India had some connections with extinction of Dinosaurs. Once again, the Indian Subcontinent had something to do with evolution! Aha… so Toba, the supervolcano was not the first major Asian player in the game of evolution….65 million years old Deccan eruptions were also played a key role in evolution.

I may have confused some of you but readers, this is exciting! Lets get back to the point…I believe that the Indian Subcontinent is one of the most richest areas that may hold clues about our past. Why? Because one, it has been part of a lot of major events such as the “Out of Africa” migration–when early humans migrated out of Africa to Australia through the coastal route, they are supposed to have traveled through India to Andaman Islands and Indonesia. Two, the Indian subcontinent has also witnessed the eruption of super volcano Toba which is believed to have wiped out the entire human population of the Indian subcontinent, brought ice age in Europe, and created the largest bottleneck in human history. Despite the richness, there have been very little scientific expeditions that have ventured the Indian Subcontinent. If more research were to be done in that corner of the world, more clues could be found out.

Time’s article proves my point. Gerta Keller, a Princeton Paleontologist took her research to India and has proposed that the Deccan eruptions “began perhaps half a million years before the mass extinction [of the Dinosaurs].” The asteroid impact catalyzed the Deccan eruptions which “reached their climax [300,000 years later], sealing the dinosaurs’ fate.”

Of course, some scientists refute this claim and it may be refutable. May be it is not the only player in Dinosaur extinction but no doubt, this finding has added valuable knowledge to our understanding of our past. Many more of these findings can allow us to better understand our past so folks, we need to revisit the Indian subcontinent more often!