Difference WikiBiology

Difference Between Autosomes and Sex Chromosomes

Main Difference

The main difference between Autosomes and Sex Chromosomes is that Autosomes are usually taken part in defining the somatic types of an organism, whereas, Sex Chromosomes are generally taken part in establishing the sex of an individual and sex-linked hormonal characters.

Autosomes vs. Sex Chromosomes

Autosomes usually determine the characters of an individual, and all males and females consist of some type of autosomes; on the other hand, sex chromosomes typically determine the gender of an individual, and all males and females contain different sex chromosomes according to their form, size, and behavior. Autosomes are generally categorized according to numbers ranging from 1 to 22; on the contrary, sex chromosomes are usually written with letters as ZW, XY, ZO, and XO.

ADVERTISEMENT

The autosomes are considered most of the chromosomes which are present inside the genome; on the flip side; sex chromosomes are found a few of the chromosomes which are available inside a genome. The 22 sets of autosomes in humans are homologous, while at the same time, sex chromosomes in females are said to be homologous, and sex chromosomes in males are referred to as non-homologous.

The position of centromere in autosomes is the same because autosomes are homomorphic; on the other hand, the location of centromere in male sex chromosomes is not alike because they are heteromorphic while the position of centromere in female sex chromosomes is alike because they are homomorphic.

ADVERTISEMENT

About 200 to 200 number of different genes are present in autosomes, and the chromosome 1 in humans which is known to be the largest contains approximately 2800 genes; in contrast, the X sex chromosome consists of more than 300 types of genes, and y sex chromosome consists of merely a few examples of genes because it is relatively small in size.

Comparison Chart

AutosomesSex Chromosomes
The chromosomes that define all the features other than the sex-determining chromosomes are known as autosomes.The chromosomes that usually establish the sex of an individual are known as sex chromosomes.
Determination
Usually, determine the characters of an individual, and all males and females consist of some type of autosomes.Typically determine the gender of an individual, and all males and females contain different sex chromosomes according to their form, size, and behavior.
Labeling
Categorized according to numbers ranging from 1 to 22Written with letters as ZW, XY, ZO, and XO
Availability
Are considered most of the chromosomes which are present inside the genomeAre considered a few of the chromosomes which are available inside a genome
Homogeneity
The 22 sets of autosomes in humans are homologous.Sex chromosomes in females are said to be homologous, and sex chromosomes in males are referred to as non-homologous.
Position of the Centromere
The position of the centromere is the same because autosomes are homomorphic.The location of centromere in male sex chromosomes is not alike because they are heteromorphic while the position of centromere in female sex chromosomes is alike because they are homomorphic.
Number of Genes
About 200 to 200 number of different genes are present, and chromosome 1 in humans, which is known to be the largest, contains approximately 2800 genes.The X sex chromosome consists of more than 300 types of genes, and y sex chromosome consists of merely a few types of genes because it is relatively small in size.
Genetic Disorders
The Mendelian inheritance is shown by autosomal disorders.The non-mendelian inheritance is shown by sex-linked disorders.
Height of the Homologous Pairs
Both chromosomes are considered of the same height in autosomal pairs.The y chromosome is considered shorter.
Number of Pairs in the Human Genome
22 pairsOne pair
Total Amount of Chromosomes in the Human Genome
44 chromosomesTwo chromosomes
ADVERTISEMENT

What are Autosomes?

The autosomes are recognized as chromosomes which are other than the sex chromosomes, and usually define the attribute of an individual. Autosomes represent the somatic characters of an organism, so they are also called somatic chromosomes.

A genome primarily contains autosomes in large numbers. For instance, in the human body, 46 chromosomes are present within a genome, and in which 44 of them are known as autosomes. A total of 22 autosomes are present in the form of homologous pairs, and they are recognized in the human genome.

Both autosomal pairs of chromosomes consist of similar genes, which are mainly organized in the same direction. An autosomal pair of the chromosome is considered different from other pairs of autosomal chromosomes in the same genome. The pairs of autosomes are categorized in the form of digits ranging from 1 to 22, consistent with the base-pair sizes present in each chromosome.

What are Sex Chromosomes?

The two pair of chromosomes other than the autosomal chromosomes which govern the sex of an organism is known as sex chromosomes which are also called as allosomes. The determination of sex is mostly occurring in plants and animals. In humans, only two sex chromosomes are present out of 46 in their genome, which is considered as Y and X chromosomes.

The female organism is characterized due to the presence of XX chromosomes, and the male body is characterized by the presence of XY chromosomes. The female consist of two similar copies of sex-determining chromosomes, which are arranged in the same way in both the X chromosomes.

That is why female sex chromosomes are considered as homomorphic, and they are homologous to each other. The male consists of two different copies of sex-determining chromosomes, so they are regarded as heteromorphic and are non-homologous to each other.

Key Differences

  1. The primary function of autosomes is that they regulate the traits of organisms. The males and females usually consist of the same replica of autosomes; on the flip side, the primary function of sex chromosomes is that they define the gender of an organism, and they are present differently in males and females through their variability in their form, size, and behavior.
  2. Autosomes are generally characterized with digits varying from 1 to 22; on the other hand, sex chromosomes are characterized with alphabets as ZW, XY, ZO, and XO.
  3. A total of 22 pairs of autosomes that are present in humans are homologous; at the same time, the female sex chromosomes are known as homologous because they contain XX chromosomes, while male sex chromosomes are known as non-homologous chromosomes because they contain XY chromosomes.
  4. Many chromosomes that are present in genome are referred to as autosomes; in contrast, a few numbers of chromosomes present in a genome are referred to as sex chromosomes.
  5. The number of genes present in autosomes is varying from 200 to 2000. The most massive chromosome one is present in humans, which contains about 2800 genes; on the contrary, in sex chromosomes, the X sex chromosome contains beyond 300 genes, and the Y sex chromosome consists of only a few numbers of genes because it is considered comparatively small in size.
  6. The Mendelian inheritance is presented by autosomal disorders, whereas the non-mendelian inheritance is displayed by sex-linked diseases.

Conclusion

The above discussion concludes that autosomes are homomorphic chromosomes, and they determine the trait of an organism; in contrast, the sex chromosomes are heteromorphic and as well as homomorphic, and they characteristically determine the sex of an individual.

Janet White

Janet White is a writer and blogger for Difference Wiki since 2015. She has a master's degree in science and medical journalism from Boston University. Apart from work, she enjoys exercising, reading, and spending time with her friends and family. Connect with her on Twitter @Janet__White