Saturday, June 3, 2017

The Blessings of learning out our Ancestors Medical History

Using clues from the past to solve your Grandchildren's medical problems

Death Certificates are not necessarily a depressing document.  Some people do not like to look for Death Certificates because they feel like it is morose subject.   Others have found that just a glimpse to the past, will help them fix the problems that may arise because of a hereditary gene that may predispose them or their children to a disease that killed an ancestor...or several ancestors.

In my family, looking at the death certificates, the most were some form of cancer - mostly lung (from smoking or being around second hand smoke),  colon cancer (from years high fat diet), and coronary problems (many uncles and father had quadruple bypass surgeries).

I know of other families where the grandparent's doing family research helped solve a cancer problem in the kidneys that plagued their family for decades.  The only way the doctor knew it was hereditary was because of the diligent efforts of mapping by documentation of death certificates.

Some mental and nervous conditions in prior decades were from consanguineous relations or marrying a cousin or sibling and then bearing children.

Interesting articles
Diseases by inbreeding started to clear up after 1865.  Until then, it was not against the law to marry a cousin in 13 states.   By having a gene pool which is narrow, allows for diseases such as:

Laws regarding first-cousin marriage in the United States
  First-cousin marriage is legal
  Allowed with requirements or exceptions
  Banned with exceptions1
  Statute bans first-cousin marriage1
  Criminal offense1
The following is from:
In 1846, Massachusetts Governor George N. Briggs appointed a commission to study "idiots" in the state, and this study implicated cousin marriage as responsible for idiocy. Within the next two decades, numerous reports (e.g., one from the Kentucky Deaf and Dumb Asylum) appeared with similar conclusions: that cousin marriage sometimes resulted in deafnessblindness, and idiocy. Perhaps most important was the report of physician Samuel Merrifield Bemiss for the American Medical Association, which concluded cousin inbreeding does lead to the physical and mental depravation of the offspring". Despite being contradicted by other studies like those of George Darwin and Alan Huth in England and Robert Newman in New York, the report's conclusions were widely accepted.[23]
These developments led to 13 states and territories passing cousin marriage prohibitions by the 1880s. Though contemporaneous, the eugenics movement did not play much of a direct role in the bans. George Louis Arner in 1908 considered the ban a clumsy and ineffective method of eugenics, which he thought would eventually be replaced by more refined techniques. By the 1920s, the number of bans had doubled.[5] Since that time, Kentucky (1943), Maine (1985) [ETA: First cousin marriage is legal in Maine so long as the couple undergoes genetic counseling to ensure that – should the couple wish to have children - there is little-to-no risk of serious health defect], and Texas (2005) have also banned cousin marriage. The National Conference of Commissioners on Uniform State Laws unanimously recommended in 1970 that all such laws should be repealed, but no state has dropped its prohibition.[3][10][24]

The following is from:,_Consanguinity_and_Inherited_Diseases


Inbreeding describes the mating between two blood relative (consanguineous relatives), the degree of inbreeding is normally measure Coefficient of Inbreeding. The value of this coefficient is equal to the probability that an individual will have inherit 2 alleles of a gene that are "identical by descent" (the same form of an allele inherited from a single common ancestor). The coefficient is of medical significant when considering autosomal recessive conditions and genetic load. The phenomenon by which the number of individuals affected by autosomal recessive disorders increases due to inbreeding is referred to as inbreeding depression and results in the reduction of the overall fitness of a population.
Inbreeding is used to create inbred strains of rats and mice (normally requires 20 generations of inbreeding) which are genetically identical. Members of the inbred stain can be genetically altered normally by knocking out or altering a single gene to observe its effect. They have provided a large deal of information about the function of specific genes.


A consanguineous marriage/mating is considered as being between two individuals who are 1st to 4th degree relatives, when considering 1st degree relatives the term incestuous marriage/mating (or simply incest) is often used. The degree to which two people are related is usual measured via the Coefficient of Relatedness which is also referred to as the coefficient of consanguinity. The value generated represents the proportion of identical by descent alleles that two individuals will share.
Degree of RelationshipExample of relativeCoefficient of Relatedness
1stBrother, Sister, Mother, Father, Daughter, Son1/2
2ndGrandfather, Grandmother, Granddaughter, Grandson, Nephew, Uncle1/4
3rdGreat Grandfather, Great Granddaughter, Cousins, Great Nephew1/8
4thGreat Great Grandfather, Great Great Grandson, Great Great nephew1/16
In a normal population only about 1% of marriages will be consanguineous however in some isolated small populations this level can increase to in excess of 40%. This level of inbreeding also occurs after events that cause large reductions in a number of individuals in a population, such events are referred to as bottle neck events.

Inherited Diseases

Mendel identified two patterns of inheritance of traits which he explained as being due to some alleles being dominant while others are recessive, explained by his Laws of Inheritance. The patterns of inheritance were seen to only be accurate for autosomes and not genes carried on the sex chromosomes therefore diseases inherited in a manner true to either of the patterns are referred to as autosomal dominant or autosomal recessive. In addition to being inherited in a mendelian fashion some disease display Extrachromosomal and Non-Mendelian Inheritance.
Autosomal RecessiveAutosomal DominantX linked RecessiveX linked DominantImprintingMitochondrialMultifactorial
AlbanismOsteogenesis imperfectaHemophilia AVitamin D Resistant RicketsAngelman SyndromeLeber's hereditary optic neuropathyCrohn's Disease
Sickle Cell AnemiaAchondroplasiaHemophilia BIncontinentia PigmentiPrader-Willi SyndromeDiabetes mellitus and deafnessAutism
Cystic FibrosisHuntington's DiseaseX linked Colour BlindnessRett SyndromeDiabetes Mellitus
PhenylketonuriaFamilial HypercholesterolemiaDuchenne Muscular Dystrophy


Related Articles


  • Křenova D., Otová B., (2009), How To Practise Biological And Medical Genetics, Karolinum Press, Prague, Czech Republic
  • Passarge E., (2007), Color Atlas of Genetic, Third Edition, Theime, New York, USA

The following is from:

Down Syndrome caused by too close gene pools?  Here's a great answer as to why genetic testing can allay all your fears.  
Originally posted by kel0212:
I hope i'm not bothering you with a very trival question, but i need to know the answer to this question before i can make an important decision in my life.... Is there scientific prove or explainations that says that there are an increase chances of giving birth to childrens with down syndrome when the parents are first cousins or are closely related in blood ties ? i know this may be maybe a stupid question but i have heard from frens that this might be true, and i just want more information and facts on it. Thanks for spending the time reading my email and regards.

First cousins do not have an increased chance in having children with Down syndrome just by virtue of being first cousins. However there are people who have an increased chance of translocations but this usually isn't known until after the first or second baby with DS is born. If you know of a number of Down syndrome births in your parents' families, it would be a good idea to go to a high-risk prenatal department of a university hospital and ask to be tested to see if you are a carrier. This is also true for a number of other conditions. In the case of close relatives...there is the chance that both parents may have inherited genes that together will double the chances that some disease will be passed on to their children. Your questions should be taken to a genetic-counsellor.

Read more:

True story from my own family from Oklahoma.  In the 1920s, Great Uncle Clarence Collins married a first cousin.  The Doctor told them they couldn't have children.  A cousin that I met in the search of more information on my family said with a southern drawl over the phone, "Now, you know the story about Uncle Clarence, right?"  I did know the story from my relative's perspective, so I said, "What story do YOU know?"  She said, "Well, the Doctor told them that they couldn't have children, and do you know, they had 10 children.  Now, none of them lived very long, but they sure showed that Doctor that they could have children!"  I said, " I heard a similar story, but I heard that because they were first cousins, and the complications that could arise from intermarrying, not that they COULDN"T have children....but that they SHOULDN'T.

I hope this sheds some light on some very controversial talking points.

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