A gene is a part of the DNA.
Alleles on the other hand refer to different versions of the same gene. There
are other more subtle differences between the two and this is what we are going
Genes are the different parts of the DNA
that decide the genetic traits a person is going to have. Alleles are the
different sequences on the DNA-they
determine a single characteristic in an individual.
Another important difference between the two is that alleles occur in pairs.
They are also differentiated into recessive and dominant categories. Genes do
not have any such differentiation.
An interesting difference between alleles and genes is that alleles produce
opposite phenotypes that are contrasting by nature. When the two partners of a
gene are homogeneous in nature, they are called homozygous. However, if the pair
consists of different alleles, they are called heterozygous. In heterozygous
alleles, the dominant allele gains an expression.
The dominance of a gene is determined by whether the AA and Aa are alike
phenotypically. It is easier to find dominants because they express themselves
better when they are paired with either allele.
Alleles are basically different types of the same gene. Let me explain this
to you in this way- If your eye colour was decided by a single gene, the colour
blue would be carried by one allele and the colour green by another. Fascinating,
All of us inherit a pair of genes from each of our parents. These genes are
exactly the same for each other. So what causes the differences between
individuals? It is the result of the alleles.
The difference between the two becomes more pronounced in the case of
traits. A trait refers to what you see, so it is the physical expression of the
genes themselves. Alleles determine the different versions of the genes that we
see. A gene is like a machine that has been put together. However, how it will
works will depend on the alleles.
Both alleles and genes play an all important role
in the development of living forms. The difference is most colourfully manifest
in humans of course! So next time you see the variety of hair colour and eye
colour around you, take a moment and admire the phenomenal power of both the gene
and the allele!
Genes are something we inherit from our parents - alleles determine how they are
expressed in an individual.
2. Alleles occur in pairs but there
is no such pairing for genes.
3. A pair of alleles produces
opposing phenotypes. No such generalisation can be assigned to genes.
4. Alleles determine the traits we
5. The genes we inherit are the
same for all humans. However, how these manifest themselves
is actually determined by alleles.