Chromosome

In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.

What is a Chromosome?

Chromosomes are the basic building blocks of life where the entire genome of an organism is essentially organized and stored in the form of DNA (deoxyribonucleic acid) which is present inside every cell making up that organism. A chromosome is a single chain of DNA that is coiled and super coiled to form dense thread-like pieces. The term chromosome is derived from the Greek words "chroma" or color and "some" or body and is so named because chromosomes have the ability to be stained with dyes.

What is the X Chromosome?

Common Chromosomal Disorders (Chromosomes 1-5 and X and Y)

What is Chromosome 2?

Human Chromosomes

What is Chromosome 3?

What is Chromosome 4?

Chromosome Karyotype

Chromosomes in Prokaryotes

Chromosomal Abnormalities

What is Chromosome 5?

What is the Y Chromosome?

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Chromosome History

Chromosomes in Eukaryotes

What is Chromosome 1?

Latest Chromosome News and Research

Novel tool offers a glimpse into the black box of ALT in aggressive cancers

Each time a cell divides, a small section of each chromosome's protective cap - the telomere - is worn away. Most cells use an enzyme called telomerase to help mitigate this loss, but 10% to 15% of cancers have another mechanism called the alternative lengthening of telomeres (ALT) pathway.

4 Jul 2025

Breakthrough AI uncovers promising Rett syndrome treatment

Rett syndrome is a devastating rare genetic childhood disorder primarily affecting girls. Merely 1 out of 10,000 girls are born with it and much fewer boys.

2 Jul 2025

How 50,000 years of ancestry shaped India’s unique disease patterns

Scientists sequenced the genomes of 2,762 individuals across India, revealing the country’s unique ancestral makeup and a wealth of previously undocumented disease-related gene variants. The study highlights how ancient migrations, founder effects, and endogamy have shaped both diversity and disease risk in India.

29 Jun 2025

Proteome imbalance from aneuploidy linked to mitochondrial dysfunction

It has been known for several years that abnormal chromosome numbers lead to protein imbalances in the affected cells. Researchers at RPTU have now investigated the detailed effects of such imbalances.

27 Jun 2025

Using machine learning to map brain aging at the cellular level

In a comprehensive Genomic Press interview, Stanford University researcher Eric Sun reveals how machine learning is revolutionizing our understanding of brain aging at an unprecedented cellular resolution.

24 Jun 2025

New genomic test predicts chemotherapy resistance in cancer patients

Chemotherapy seeks to destroy tumor cells and has been a standard treatment for cancer for decades.

24 Jun 2025

Scientists discover on/off gene switches that could revolutionize personalized medicine

Scientists identified 473 human genes that act as genetic “on/off switches,” shaping disease risk through tissue-specific or universal patterns regulated by DNA changes and hormones. These findings could pave the way for more precise diagnostics and personalized therapies across cancers, immune, skin, and metabolic diseases.

22 Jun 2025

Histone modification involved in chromosome and spindle stabilization in mouse oocytes

The accurate distribution of chromosomes in an oocyte is essential for the correct transmission of genetic information to the next generation.

20 Jun 2025

Study finds high levels of iron in the brains of people diagnosed with Down syndrome and Alzheimer's

Scientists at the USC Leonard Davis School of Gerontology have discovered a key connection between high levels of iron in the brain and increased cell damage in people who have both Down syndrome and Alzheimer's disease.

19 Jun 2025

New hereditary condition impairs DNA repair and raises blood cancer risk

A new hereditary condition has been discovered that affects patients' ability to repair DNA – leaving them both at greater risk of developing blood cancer, and unable to repair some of the damage caused by chemotherapy treatments.

16 Jun 2025

Maternal iron deficiency disrupts embryonic sex determination in mice

Developmentally expressed genes play a fundamental role in the formation of a wide range of organs. The Y chromosome-located mammalian sex-determining gene Sry, required for the formation of testis, is activated only within a narrow time window during embryogenesis.

11 Jun 2025

Uncovering the genetic link between type 2 diabetes and brain structure

Type 2 diabetes mellitus (T2DM) is a highly prevalent metabolic disorder worldwide. Beyond glucose dysregulation, it exerts significant effects on the central nervous system.

11 Jun 2025

Dog exposure may lower genetic risk of eczema in children

New research published in Allergy indicates that certain environmental exposures may affect a child's risk of developing atopic eczema, a condition characterized by dry, itchy, and inflamed skin. In other words, although some people may be genetically predisposed to eczema, certain environmental factors may increase or decrease that risk.

5 Jun 2025

Loss of Y chromosome in male immune cells linked to poorer cancer outcomes

A study initiated by a University of Arizona Comprehensive Cancer Center physician-scientist defined for the first time how loss of the Y chromosome in male immune cells negatively affects immune system function, which may explain why loss of Y is associated with lower cancer survival rates.

5 Jun 2025

Y chromosome loss linked to poor cancer outcomes

When cancer cells in male patients and immune cells in their tumors both lose the Y chromosome, those patients tend to experience poorer outcomes than patients without Y chromosome loss, according to new findings from Cedars-Sinai investigators.

4 Jun 2025

Salk researchers create detailed genetic atlas of cannabis to date

Cannabis has been a globally important crop for millennia. While best known today as marijuana for its psychoactive cannabinoid THC (tetrahydrocannabinol), historically, cannabis has been a cornerstone of human civilization, providing seed oil, textiles, and food for more than 10,000 years.

29 May 2025

Unlocking the secrets of human longevity and healthy aging

Human healthy aging and longevity are complex phenomena influenced by a dynamic interplay of genetic, epigenetic, metabolic, immune, and environmental factors.

22 May 2025

Vitamin D supplements help preserve telomere length in aging adults

Results from the VITAL randomized controlled trial reveal that vitamin D supplementation helps maintain telomeres, protective caps at the ends of chromosomes that shorten during aging and are linked to the development of certain diseases.

21 May 2025

Genetic variations in Prader-Willi syndrome offer key insights into autism and psychosis

In a comprehensive Genomic Press Invited Expert Review, researchers from the University of Haifa have synthesized cutting-edge findings on Prader-Willi syndrome (PWS), revealing how this complex neurodevelopmental disorder serves as a critical model for understanding the interplay between autism spectrum disorder (ASD) and psychotic spectrum disorders (PSD).

20 May 2025

New gene editor evoCAST enables precise insertion of complete genes

Ask scientists what gene editing tool is most needed to advance gene therapy, and they'd probably describe a system that's now close to realization in the labs of Samuel Sternberg at Columbia University Vagelos College of Physicians and Surgeons and David Liu at the Broad Institute of MIT and Harvard.

15 May 2025