Jacob worth Noble Prize  in Biology

    Dr. Reuven Reuveni - Israel
October 10, 2013

 

 

 

 

 

Jacob, Rachel, Lea and Laban – the Start - Up Period

 Worth a Noble Prize in Biology

Genesis 32:13-15

 

If Noble Prize were available, Jacob the father of the Twelve Tribes and the Jewish People would have been the winner in Biology and Economy

Story in three episodes – EPISODE ll

 

Jacob's Journey from Refugee Son to Patriarch in three episodes

 

In three weekly portions we read in Genesis the story of Abraham, the father of the monotheism, the believe in one God and therefore the strong personality who brought to the world the foundation of the Judaism, Christianity and Islam. In one weekly portion we read about Isaac his son and seven chapters - almost 20% of Genesis, are devoted to tell us the magnificent story of Jacob – the father of the Jewish People.

 

 

Seven years for Leah and seven for Rachel. In practical means, his work was to take care of Laban's great herds and flocks which fed in the broad pastures about Haran, being led at times a journey of some days away from home. These were the simple facts as the bible tells us. Is it was so simple and naïve indeed?

 

Practically, during fourteen years Jacob performed breeding experiments and over the years he was the first to elucidate and implemented the Low of Heredity that thousands years later will be known as The Mendel Lows of Heredity.

Mendel's Laws

The theories of heredity attributed to Gregor Mendel, based on his work with pea plants, are well known to students of biology. But his work was so brilliant and unprecedented at the time it appeared that it took thirty-four years for the rest of the scientific community to catch up to it. The short monograph, Experiments with Plant Hybrids, in which Mendel described how traits were inherited, has become one of the most enduring and influential publications in the history of science

Mendel's research reflected his personality. Once he crossed peas and mice of different varieties "for the fun of the thing," and the phenomena of dominance and segregation "forced themselves upon notice." He saw that the traits were inherited in certain numerical ratios. He then came up with the idea of dominance and segregation of genes and set out to test it in peas. It took seven years to cross and score the plants to the thousand to prove the laws of inheritance! From his studies, Mendel derived certain basic laws of heredity: hereditary factors do not combine, but are passed intact; each member of the parental generation transmits only half of its hereditary factors to each offspring (with certain factors "dominant" over others); and different offspring of the same parents receive different sets of hereditary factors. Mendel's work became the foundation for modern genetics.

The impact of genetic theory is no longer questioned in anyone's mind. Many diseases are known to be inherited, and pedigrees are typically traced to determine the probability of passing along an hereditary disease. Plants are now designed in laboratories to exhibit desired characteristics. The practical result of Mendel's research is that it not only changed the way we perceive the world, but also the way we live in it.

Mendel discovered that when crossing white flower and purple flower plants, the result is not a blend. Rather than being a mix of the two, the offspring was purple flowered. He then conceived the idea of heredity units, which he called "factors", one of which is a recessive characteristic and the other dominant. Mendel said that factors, later called genes, normally occur in pairs in ordinary body cells, yet segregate during the formation of sex cells. Each member of the pair becomes part of the separate sex cell. The dominant gene, such as the purple flower in Mendel's plants, will hide the recessive gene, the white flower. After Mendel self-fertilized the F1 generation and obtained the 3:1 ratio, he correctly theorized that genes can be paired in three different ways for each trait: AA, aa, and Aa. The capital "A" represents the dominant factor and lowercase "a" represents the recessive. The last combination listed above, Aa, will occur roughly twice as often as each of the other two, as it can be made in two different ways, Aa or aA.

Mendel stated that each individual has two factors for each trait, one from each parent. The two factors may or may not contain the same information. If the two factors are identical, the individual is called homozygous for the trait. If the two factors have different information, the individual is called heterozygous. The alternative forms of a factor are called alleles. The genotype of an individual is made up of the many alleles it possesses. An individual's physical appearance, or phenotype, is determined by its alleles as well as by its environment. An individual possesses two alleles for each trait; one allele is given by the female parent and the other by the male parent. They are passed on when an individual matures and produces gametes: egg and sperm. When gametes form, the paired alleles separate randomly so that each gamete receives a copy of one of the two alleles. The presence of an allele doesn't promise that the trait will be expressed in the individual that possesses it. In heterozygous individuals the only allele that is expressed is the dominant. The recessive allele is present but its expression is hidden.

Mendel summarized his findings in two laws; the Law of Segregation and the Law of Independent Assortment.

 

Law of Segregation - The "First Law"

The Law of Segregation states that every individual possesses a pair of alleles for any particular trait and that each parent passes a randomly selected copy allele of only one of these to its offspring. The offspring then receives its own pair of alleles for that trait. Which  ever of the two alleles in the offspring is dominant determines how the offspring expresses that trait e.g. the color of a plant, the color of an animal's fur, the color of a person's eyes.

Law of Independent Assortment - The "Second Law"

The Law of Independent Assortment, also known as "Inheritance Law" states that separate genes for separate traits are passed independently of one another from parents to offspring. That is, the biological selection of a particular gene in the gene pair for one trait to be passed to the offspring has nothing to do with the selection of the gene for any other trait. More precisely the law states that alleles of different genes assort independently of one another during gamete formation. While Mendel's experiments with mixing one trait always resulted in a 3:1 ratio  between dominant and recessive phenotypes, his experiments with mixing two traits, dihybrid cross, showed 9:3:3:1 ratios. But the 9:3:3:1 table shows that each of the two genes are independently inherited with a 3:1 phenotypic ratio. Mendel concluded that different traits are inherited independently of each other, so that there is no relation, for example, between a cat's color and tail length.

Again, Mendel's research reflected his personality. Once he crossed peas and mice of different varieties "for the fun of the thing," and the phenomena of dominance and segregation "forced themselves upon notice." He saw that the traits were inherited in certain numerical ratios. He then came up with the idea of dominance and segregation of genes and set out to test it in peas.

It took seven years to cross and score the plants to the thousand to prove the laws of inheritance! From his studies, Mendel derived certain basic laws of heredity: hereditary factors do not combine, but are passed intact; each member of the parental generation transmits only half of its hereditary factors to each offspring, with certain factors "dominant" over others; and different offspring of the same parents receive different sets of hereditary factors. Mendel's work became the foundation for modern genetics.  Is it was really so?

Following is the story as we read in Genesis 30: 37-41

 

37 And Jacob took him rods of fresh poplar, and of the almond and of the plane-tree; and peeled white streaks in them, making the white appear which was in the rods.

38 And he set the rods which he had peeled over against the flocks in the gutters in the watering-troughs where the flocks came to drink; and they conceived when they came to drink.

39 And the flocks conceived at the sight of the rods, and the flocks brought forth streaked, speckled, and spotted.

40 And Jacob separated the lambs--he also set the faces of the flocks toward the streaked and all the dark in the flock of Laban--and put his own droves apart, and put them not unto Laban's flock.

41 And it came to pass, when so ever the stronger of the flock did conceive, that Jacob laid the rods before the eyes of the flock in the gutters, that they might conceive among the rods;

42 but when the flock were feeble, he put them not in; so the feebler were Laban's, and the stronger Jacob's.

43 And the man increased exceedingly, and had large flocks, and maid-servants and men-servants, and camels and asses.

 

"And Jacob took his rods of green poplar, and of the hazel and chestnut tree; and pilled white starks in them, and made white appear which was in the rods. And he set the rods which he had pilled before the flocks in the gutters in the watering troughs when the flocks came to drink, that they should conceive when they came to drink. And flocks conceived before the rods, and brought forth cattle ring-straked, speckled and spotted. And Jacob did separated the lambs" Genesis 30: 37-41.

 

In fact, the first breeding program ever reported, according to Feliks (*), was thoughtfully conducted by Jacob when he was serving his father-in-law, Laban, in order to obtain his young and beautiful second wife, Rachel. In the above verses from Genesis, the "markers" on the rods of green poplar, hazel, and chestnut that Jacob had been using in the field were simply a means of masking his keen perception of the laws of heredity that he practiced as a "clever" breeding program. These "markers" on the rods were simply to avoid the possibility that one can mimic his real breeding program or follow his long term research that he has been doing. Jacob apparently knew that the hybrids derived from white sheep and black goats, which carried recessive genes of "spottedness", matured sexually earlier than the pure monochromes in the flock. He mated the hybrids (black and white animals), and their recessive genes emerged to produce maximally spotted offspring in each generation, a process that thousands of years later was to be scientifically reported and documented in the Mendelian Laws of Heredity, see Reuveni, R**). .(    

Again, it took seven years to cross and score the plants to the thousand to prove the laws of inheritance! From his studies, Mendel derived certain basic laws of heredity, for Jacob it took fourteen years though!!!  Assuming that practically, during fourteen years Jacob performed breeding experiments through which he could anticipate the color and shape of the goats and sheep fur and therefor over the years he was the first to elucidate and implemented the Lows of Heredity. Now Jacob is ready to conduct his Exit Part – the agreement with Laban, regarding his expected wages for the next six years period to work for him. His success for the next six years is obvious and no doubt.

 

·         Felix, Y. Relation between heredity and environment, in Nature and man in the Bible, by Felix, Y. Soncino Press, London, 1981, 294p

·         Reuveni, R. Biochemical markers as tools to screening resistance against plant pathogens, 21- 47, in Noble approaches to integrated pest management, by Reuveni R. Ed. Lewis Publishers, Boca Raton, 1995   

 

 

 

To be continued in Episode |||…….