How can I verify my true genetic relationship with my close relatives with simple physical traits?
Here are the answers for your four questions:


Widow's peak (hair in V): dominant: Dominant and recessive characteristics, blinn.edu; Dominant Inheritance, Genetics Generation
Dimples: irregular; tendancy toward dominant *: Mendelian Genetics, uni.edu; What Is the Genotype for Dimples?, seattlepi.com; Understanding Genetics, genetics.thetech.org
Curling tongue: complex; tendancy toward dominance: Myths of Human Genetics, udel.edu; Debunking the biggest genetic myth of the human tongue, Cathrine Woods
Phenylthiocarbamide detection: dominant: Phenylthiocarbamide tasting, Encyclopedia Britannica; Genetic study of phenylthiocarbamide (PTC) taste perception, Egyptian Journal of Medical Human Genetics, Volume 13, Issue 2; PTC The Genetics of Bitter Taste, genetics.utah.edu


Hope it helps!

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