Medicine
Geneticists study the hereditariness of properties of living beings and humans. Some diseases are transmitted only from parents to children. Hemophilia is a well-known example.
All living beings have their properties coded in genes DNA on the chromosomes in the nucleus of every single cell. Chromosomal and Mitochondrial DNA analysis is able to provide strong evidence in proving or refuting close bloodrelationship through females among individuals.
History
- Demographers are interested in the extent of populations in the past.
- Social historians are interested in the evolution of living conditions.
- Prosopographers describe a group of related individuals (e.g. family related) in the historical context of their time and place in society.
All these historians often consult the same historical sources as genealogists do.
Auxiliary sciences to history, such as sigillography (the study of seals) and heraldry (the study of coat of arms) are closely related to genealogy too.
Genetics is the scientific study of how physical, biochemical, and behavioral traits are transmitted from parents to their offspring.
Geneticists are able to determine the mechanisms of inheritance because the offspring of sexually reproducing organisms do not exactly resemble their parents, and because some of the differences and similarities between parents and offspring recur from generation to generation in repeated patterns.
The science of genetics began in 1900, when several plant breeders independently discovered the work of the Austrian monk Gregor Mendel, which, although published in 1866, had been virtually ignored. Working with garden peas, Mendel described the patterns of inheritance in terms of seven pairs of contrasting traits that appeared in different pea-plant varieties. He observed that the traits were inherited as separate units, each of which was inherited independently of the others (MENDEL'S LAWS). He suggested that each parent has pairs of units but contributes only one unit from each pair to its offspring. The units that Mendel described were later given the name genes.
Most physical characteristics of humans are influenced by multiple genetic variables as well as by the environment. Some characteristics, such as height, have a relatively large genetic component. Others, such as body weight, have a relatively large environmental component.
Still other characteristics, such as the blood groups and the antigens involved in the rejection of transplanted organs, appear to involve entirely genetic components; no environmental condition is known to change these characteristics.
Susceptibility to various other diseases has an important genetic element. These diseases include schizophrenia, tuberculosis, malaria, several forms of cancer, migraine headaches, and high blood pressure. Many rare diseases are caused by recessive genes and a few by dominant genes.
The identification and study of genes are of great interest to biologists, and are also of medical importance when a particular gene is involved in disease. The human genome contains approximately 50,000 to 100,000 genes, of which about 4000 may be associated with disease. A coordinated effort, called the Human Genome Project, was started in 1990 to characterize the entire human genome.
The primary goal of the Human Genome Project is the generation of various genome maps, including the entire nucleotide sequence of the human genome. The Human Genome Project has been greatly assisted by the ability to clone large fragments of DNA into yeast artificial chromosome vectors for further analysis, and the automation of many techniques such as DNA sequencing.
Hemophilia is a blood disease, due to a recessive gene on one of the chromosomes. The disease only affects male individuals, but females can transport the disease to their children. The disease is a deficiency in the clotting of the blood which causes severe bleeding at the slightest wound.
Royal hemophilia so far has afflicted nine male descendants of Queen Victoria, including the tsarevitch Alexis Romanov and an uncle of the present King of Spain, the Prince of the Asturias, who hemorrhaged to death after a car accident in 1938.
The original mutation of the gene, which was inherited by one of Queen Victoria's four sons and two of her four daughters, is believed to have occured in the X chromosome of her father, Edward, Duke of Kent. When Victoria was born in 1819, Prince Edward was 52, and the germ cells of older men are more prone to some types of mutation.
The execution of tsar Nicholas and his family and the untimely death of two afflicted Prussian princes have eliminated the mutant gene from Victoria's Hesse line, but it may still be carried recessively by some of her English and Spanish female descendants.
Chromosomal and Mitochondrial DNA analysis
The analysis of familial relationships by DNA analysis has a brief but eminent history to date.
Chromosomal DNA is used to identify the sex of a person, by focusing on the X-Y homologous gene amelogenin. Other parts to the DNA are used to demonstrate close blood relationship between individuals. (so called Short Tandem Repeat loci). Maternal line relations between individuals can be proven from the mitochondrial DNA: mitochondrial DNA is only inherited in straight female line.
In 1991 a murder victim was identified by DNA analysis of the sketetal remains by comparing the DNA with that of the supposed parents.
The same scientists also identified the bones of the nazi-criminal Josef Mengele., by comparing the DNA with that of his living wife and son. (the world can rest assured, he is dead all right...
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The Romanovs.
In 1993 bones found two years before in a shallow grave in Ekaterinenburg in Russia, were identified as the remains of the last Tsar, Tsarina and three of their five children, the royal physician and three servants. To prove relationship with the Romanov family, the DNA extracted and amplified by polymerase chain reaction, was compared to a blood sample provided by Prince Philip, Duke of Edinburgh, husband of Queen Elisabeth the second of England, and a grand nephew of the tsarina.
Soon after, Anna Anderson Manahan, a US immigrant, deceased in 1984, who had claimed all her live to be the youngest daughter of the last Tsar, Anastasia, supposedly escaped from the bolshevik firing squad, was proved NOT to be who she claimed. Moreover, her DNA very closely matched that of an other immigrant from Pomerania (Germany-Poland), a great nephew of the women Franzisca Schanzkowska. Already in the 1920s a private investigator of the Grand Duke of Hesse had identified Anna Anderson with Schanzkowska.
In June 1995 mitochondrial DNA analysis has been performed by the Centrum voor Menselijke Erfelijkheid (Centre for Human Genetics) in Belgium, extracted from hair from a man called Carl Wilhelm Naundorff. (1785?-1845) All his live, he claimed to be Louis XVII, the then 8-year old unique son of King Louis XVI of France, at the time of his beheading by the French Revolutionists in 1793.
Mitochondrial DNA was compared to that from hair of two other daughters of Empress Maria Theresia of Austria, sisters of Marie-Antoinette, wife of King Louis XVI. Since mtDNA is inherited only through female line, his mtDNA should match that of his supposed aunts. In 1998 the results were communicated to the public: there is absolutely no match between Naundorff's DNA and that of the sisters of queen Marie-Antoinette.
The communication of these results inspired a French historican to have this same research institution perform a comparative DNA analysis on the heart of the boy who died in prison in 1793 as Louis XVII. His heart indeed had been cut out by the doctor who examined the deceased boy and is preserved up to this day in Paris. On a press conference in Paris, 19 April 2000 the results were communicated to the public: there is a perfect match between the DNA of the heart and that of all other DNA profiles of close or distant relatives of his mother queen Maria-Antoinette.
Samenwerkingsverband Vlaamse Verenigingen voor Familiekunde vzw
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