Human hair color account for all possible shades of brown, blond, or red (for example, platinum blond versus dark blond/light brown), nor does it explain why hair color sometimes darkens as a person ages. Several gene pairs control the light versus dark hair color in a cumulative effect. A person's genotype for a multifactorial trait can interact with the environment to produce varying phenotypes (see quantitative trait locus). Natural hair color can be brown, blond, black, red, or white; all natural hair colors including grey, white and lightest blond, are shades of brown. The Fischer–Saller scale, named after Eugen Fischer and , is
Media and LGBTQ youth of colour in the United States youth worldwide. The hashtag was used by a diverse community on a number of platforms, including Instagram, Facebook, Twitter and YouTube. Many young teens shared their stories and created an Instagram channel. Movements such as the #40toNoneDay raised awareness regarding youth-of-color homelessness, particularly in the LGBT community. Sara Ramirez, who plays a bisexual doctor on "Grey’s Anatomy", advocates the movement to bring attention to the 40 percent of homeless youth who identify as part of the LGBT community; LGBT youth are less than seven percent of the general youth population. Representations of, and expressions by, LGBTQ youth of colour can