Moles and Genetics



My dad, my sister and I we all have a mole in the exact same place (on our face). My gf, her dad and her brother all have a mole in the exact same spot (back of the head). Many people have the same birthmark in the same spot as their families. I understand this is inherited, but.. how? Does DNA work to regulate such a small detail.. a minor imperfection on the skin?

In: Biology

Absolutely! We have figured out entire chromosomes and what every part of the Dna is for. Dna works like this: There are certain molecules in a very specific order (just like a recipe). Part of the cell can read this recipe and then “cook” the amino acid. A lot of amino acids make a protein and these proteins can have a very very very different tasks in the human body. They can be part of breakin down the food you eat (we call them enzymes) or work as a tunnel for other molecules in your body (they are almost like cell-wall security. If you dont have the look to get in the cell, they wont let you pass. They are called tunnel Proteins) and many many more (just like you noticed skin building).

Lets look at it form another perspective: illnesses. People that are affected by the “Down syndrome “ have one extra chromosome (the 21st chromosome. Thats why [at least in Germany] the scientific name is “Trisomy 21”. This extra chromosome leads to many difficulties like smaller hight, the classical “squeezed face” and “brain impairment” (some might say stupid in general terms).
Lets take a look at cancer: cancer is when a cell mutates and starts to multiply like crazy. This is all because of DNA “failure “. All cells have a “kill switch” that triggers should the cell be in critical status. And this (and some other dna mutations we will leave out for now) fails because the recipe isn’t correct anymore and thus the cell can’t build it.