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.
Different versions of a gene are called alleles. Alleles are described as either dominant or recessive depending on their associated traits. 1  Since human cells carry two copies of each chromosome they have two versions of each gene.2  These different versions of a gene are called alleles. 3  Alleles can be either dominant or recessive.ifferent versions of a gene are called alleles. Alleles are described as either dominant or recessive depending on their associated traits. 1  Since human cells carry two copies of each chromosome they have two versions of each gene.