Lines on palm begin to form about four weeks after conception. By the end of the fourth month the formation of lines, ridges and creases on the fingers and palms is complete, and this structure remains the same for the rest of the person's life making hands like a fossil record of our life in the uterus.
According to medical science the major lines on hands are formed within 2.5 to 3 months of period after conception. The process of formation of minute lines gets completed by 6 months. As per medical science the comprehensive knowledge of palmistry remains hidden in 21st chromosome which means that the development of our lines is completely based on genetics.
According to a research in medical science some kind of irregularity in 21st chromosome can cause mental in stability in children and it is observed that their heart line and head line merge into one. This type of child can be eccentric because according to medical science this is a symptom of fatal alcohol syndrome and genetic abnormalities.
According to medical science Head Line and Heart Line join when in the first few weeks of pregnancy the mother of child goes through some kind of mental stress or tension. It also proves that state of mind of mother can bring changes in the lines of hands of her child. This is true because genetic fact creates the lines whereas the mother's condition during pregnancy and the upbringing of child can change the health and future of the child.
As per the scieance of palmistry various areas of hand activate specific areas of brain and accordingly they are associated with various planets. For example the area below index finger is known as mount of Jupiter as this point of hand is directly connected with the knowledge area of our brain. The area below middle finger is mount of Saturn because it is related with action area of a brain. The little finger is connected with that area of our brain which remains involved in scientific calculations, therefore the area below this finger is known as mount of Mercury.
Two nerves are connected to ring finger whereas the other fingers are controlled by one nerve only. The larger area of our brain is controlled by this area only and therefore ring finger is most important among all fingers and that is why it is rightly termed as finger of Sun. Probably for this reason only, most of the gems are worn in this finger. The other important activities like pooja ceremonies, counting the beads of rosary for recitation of mantras or putting mark on forehead etc. are performed with this finger only.
One of the most fascinating things discovered about hands is the ratio between the second and fourth digit and its link to levels of testosterone and astrogen. This has become known as the "Digit Ratio" or "2D : 4D ratio", and is obtained when the length of the second (index/ 2D) finger is measured, and divided by the length of the fourth (ring/4D) finger.
This ratio has been found to be one of the only sexually dimorphic (different norms for men and women) characteristics that are fixed before puberty. Men tend to have longer fourth (ring) fingers compared to their index finger, while women have longer index fingers comparatively.
Simplified, the fourth fingers length is positively correlated to testosterone, while the second (index) finger with astrogen.
In Europeans 2D:4D ranges between 1.0 and 0.96, with females tending towards the higher values and males tending towards the lower.
Conclusion: Males with a lower 2D:4D ratios (greater fetal exposure to testosterone) have been correlated with being more fertile, more aggressive, and having higher music & sports aptitude.
Men with higher 2D : 4D ratios have been found to be more at risk for heart disease.
Male to female transsexuals were found to have a higher digit ratio than control males, but one that was comparable to control females.
Lower digit ratios in women have been correlated (but not statistically significant) with lesbian/bisexual tendencies, along with aggressiveness and assertiveness.
Women with higher digit ratios are more at risk for breast cancer, and more fertile.
Schizophrenic men and women were found to have higher digit ratios and a lower 2D:4D ratio has also been found more often in those with Autism.
Colour of Hands: Beyond digit ratio, there are other medical clues we can gather from our hands. The colour and appearance of our hands can often be a good indicator of our general health:
Poor blood circulation (a symptom for a variety of ailments) can cause hands to take on a blue-ish hue. Red hands may indicate cirrhosis of the liver.
Fingernails: Diabetes is often accompanied with "Terry's nails" (half white, half pink nails). Blue fingernails can be sign of heavy metal poisoning, (very) poor circulation, lung or heart problems. Yellow or green finger nails can indicate a respiratory problem.
Clubbing (nails curve over the fingertips) is often caused by low oxygen levels in the blood, and could be a sign of lung, liver or bowel disease. Spoon nails (concave shaped) may indicate an iron deficiency.
Fingerprints: Dermatoglyphics is the scientific study of fingerprints, and rare dermatoglyphic patterns often relate to genetic disorders.
In one study patients with Alzheimer's showed a significantly increased frequency of ulnar loops on their fingertips.
A pattern of eight or more ulnar loops was found significantly more often in patients with Alzheimer's (72%) than in the control group (26%).
Certain swirl patterns are known to be associated with genetic disorders such as Downs syndrome.
In this way our palm denotes our development and future after conception by mother.