The Truth of Dimples!

Dimples are often view as beauty and loveliness marks; however, the truth of dimples is actually resulting in genetic defects.  Most check dimples are result in genetic defects of shortened muscle- which pulls the around skin instead of around bones. It is inherited facial traits that are passed from one generation to the next.  If both parents have dimple traits the children have 50-100% chance of inheriting the gene, if only one parent has dimple traits the chance of the children inheriting the genes are 50%. Dimples can be passed down through multiple generations - Penetrance is the frequency of which a heritable trait is passed down. Many people are the carrier but didn't show the associate traits, the traits will be passing to a successive generation.  Apart from that, sometimes the dimples may cause by spontaneous mutations that result in a dent in the cheek or a cleft chin which leads to dimples. 

Genetic of eye color

                                                     Credit to: XoletteScience

Have you ever wondering why your eye color is brown, blue, green or grey? Most people will say this is because of dominant and recessive traits, where brown eye color being the dominant one. However, our eyes color is far more complicate than that, eyes color is determine by multi-gene trait, not a single-gene trait.  OCA2 and HERC2 genes are mainly responsible for eye color. OCA2 locates on chromosome 15 and controls almost ¾ of the blue-brown color spectrum. These genes control the amount of melanin (type of pigments) inside the iris. Melanin is produce in a specialized cells call melanocytes, which store in intracellular compartments known as melanosomes. A number of other genes (TYRP1, ASIP and ALC42A5) also function in the melanin pathway and shift the total amount of melanin present in the iris. Eye color is arranged from lightest blue to darker brown and everything in between; Brown contains highest level of melanin and blue contains minimal melanin. Red eyes color have no melanin so there is no pigment in the iris, the red color comes from blood vessels. In addition our eyes color change over time period, this is due to decrease or increase stroma in the pigment granules. A little fun fact, people with blue color eyes come from same ancestor. 

Global warming is killing Our Polar Bears

Picture Credit to: Encyclopedia Britannica Advocacy For Animals 

After industrial revolution began, the earth's surface temperature increased rapidly causing sea ices to melt in the Arctic. Ursus maritimus (polar bears) also often refered to as "ice bear" are suffering for this dramatic climate change. Polar bears populations are decreasing as the temperature increase. They are starving because difficulties in hunting ringed-seals- without sea ices. The book The last polar bear by Kazlowski shows polar bears are skinnier and smaller than they were in 1990. In 1990 adult male polar bears average weight was 810 pounds and now the average weight is 725 pounds, they were also older on average than the bears that were measured before 1990. Stirling points out this is the same with the female population, the average weight declined about 143 pounds from 1980 to 2004 in Western Hudson Bay. Starvation greatly impacts polar bears' reproductive and survival rates; without enough foods female polar bears find it more difficult reproduce. Jim Morrison states when female polar bears become to lean they cannot to produce milk to nurse cubs and the cubs die. If global warming is prevent, two-thirds of the world's polar bears could disappear by 2050.