Without enough thyroid hormone, metabolism slows, making weight gain more likely. Even a thyroid functioning at the lower end of the normal range might cause weight gain. Treating hypothyroidism with medication may reverse some of the weight gain. If you have any concerns, seek medical advice.
1 Allele: a different version of a gene. 2  Dominant: a trait that is visible and can cover up other traits when there is more than one present. 3  Genotype: the genetic makeup of an organism, or the versions of a gene that an organism has. 4  Heterozygous: having two different versions of a gene.
A segment of DNA is called a gene. All an organism's biological traits are the result of gene coding. Though it was once thought that one gene codes for one trait, it is now u â¦ nderstood that a gene may code for more than one trait, and genes may work with other genes to produce a trait. segment of DNA is called a gene. All an organism's biological traits are the result of gene coding. Though it was once thought that one gene codes for one trait, it is now u â¦ nderstood that a gene may code for more than one trait, and genes may work with other genes to produce a trait.