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Genetics Home Reference: your guide to understanding genetic conditions     A service of the U.S. National Library of Medicine®


Reviewed August 2013

What is the official name of the TUBA1A gene?

The official name of this gene is “tubulin alpha 1a.”

TUBA1A is the gene's official symbol. The TUBA1A gene is also known by other names, listed below.

What is the normal function of the TUBA1A gene?

The TUBA1A gene provides instructions for making a protein called alpha-tubulin (α-tubulin). This protein is part of the tubulin family of proteins that form and organize structures called microtubules. Microtubules are rigid, hollow fibers that make up the cell's structural framework (the cytoskeleton). They are composed of α-tubulin and a similar protein called beta-tubulin (β-tubulin) that is produced from a different gene. Microtubules are necessary for cell division and movement.

Most cells produce α-tubulin, but the protein is found in highest amounts in the developing brain. During brain development, α-tubulin partners with β-tubulin to form microtubules that move nerve cells (neurons) to their proper location (neuronal migration). Microtubules form scaffolding within the cell. The tubulin proteins that make up the microtubule are moved from one end of a microtubule to the other end. This protein transfer propels the microtubules in a specific direction, moving the cell.

Does the TUBA1A gene share characteristics with other genes?

The TUBA1A gene belongs to a family of genes called TUB (tubulins).

A gene family is a group of genes that share important characteristics. Classifying individual genes into families helps researchers describe how genes are related to each other. For more information, see What are gene families? ( in the Handbook.

How are changes in the TUBA1A gene related to health conditions?

isolated lissencephaly sequence - caused by mutations in the TUBA1A gene

Approximately 40 mutations in the TUBA1A gene have been found to cause isolated lissencephaly sequence (ILS). This condition is characterized by abnormal brain development that results in the brain having a smooth appearance (lissencephaly) instead of its normal folds and grooves. Individuals with ILS have severe neurological problems, including intellectual disability and recurrent seizures (epilepsy). Most of these mutations change single protein building blocks (amino acids) in the α-tubulin protein. The resulting abnormal α-tubulin cannot form microtubules or interact with other proteins. As a result, the overall function of microtubules is reduced. In the developing brain, this decrease in microtubule function impairs the normal migration of neurons and leads to a decrease in the formation of the brain's folds and grooves or a completely smooth appearance of the brain, resulting in the neurological problems characteristic of ILS.

lissencephaly with cerebellar hypoplasia - caused by mutations in the TUBA1A gene

At least 10 mutations in the TUBA1A gene have been found to cause lissencephaly with cerebellar hypoplasia (LCH). This condition affects brain development, resulting in lissencephaly and an unusually small and underdeveloped area of the brain called the cerebellum (cerebellar hypoplasia). The TUBA1A gene mutations that cause LCH change single amino acids in the α-tubulin protein. These altered proteins can still be incorporated into microtubules, but research suggests that these microtubules have decreased or abnormal function.

In the developing brain, impaired microtubule function prevents the normal migration of neurons. As a result, the normal folds and grooves of the brain do not form and the cerebellum and other brain structures do not develop properly. This impairment of brain development leads to intellectual disability, delayed overall development, movement problems, and other signs and symptoms of LCH.

Where is the TUBA1A gene located?

Cytogenetic Location: 12q13.12

Molecular Location on chromosome 12: base pairs 49,184,795 to 49,189,324

(Homo sapiens Annotation Release 107, GRCh38.p2) (NCBI (

The TUBA1A gene is located on the long (q) arm of chromosome 12 at position 13.12.

The TUBA1A gene is located on the long (q) arm of chromosome 12 at position 13.12.

More precisely, the TUBA1A gene is located from base pair 49,184,795 to base pair 49,189,324 on chromosome 12.

See How do geneticists indicate the location of a gene? ( in the Handbook.

Where can I find additional information about TUBA1A?

You and your healthcare professional may find the following resources about TUBA1A helpful.

You may also be interested in these resources, which are designed for genetics professionals and researchers.

What other names do people use for the TUBA1A gene or gene products?

  • B-ALPHA-1
  • TUBA3
  • tubulin, alpha 1a
  • tubulin alpha-1A chain
  • tubulin alpha-3 chain
  • tubulin, alpha, brain-specific
  • tubulin B-alpha-1

See How are genetic conditions and genes named? ( in the Handbook.

What glossary definitions help with understanding TUBA1A?

acids ; cell ; cell division ; cerebellum ; cytoskeleton ; disability ; epilepsy ; gene ; hypoplasia ; microtubule ; neurological ; neuronal migration ; protein

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.


  • Bahi-Buisson N, Poirier K, Boddaert N, Saillour Y, Castelnau L, Philip N, Buyse G, Villard L, Joriot S, Marret S, Bourgeois M, Van Esch H, Lagae L, Amiel J, Hertz-Pannier L, Roubertie A, Rivier F, Pinard JM, Beldjord C, Chelly J. Refinement of cortical dysgeneses spectrum associated with TUBA1A mutations. J Med Genet. 2008 Oct;45(10):647-53. doi: 10.1136/jmg.2008.058073. Epub 2008 Aug 26. (
  • Jansen AC, Oostra A, Desprechins B, De Vlaeminck Y, Verhelst H, Régal L, Verloo P, Bockaert N, Keymolen K, Seneca S, De Meirleir L, Lissens W. TUBA1A mutations: from isolated lissencephaly to familial polymicrogyria. Neurology. 2011 Mar 15;76(11):988-92. doi: 10.1212/WNL.0b013e31821043f5. (
  • Kumar RA, Pilz DT, Babatz TD, Cushion TD, Harvey K, Topf M, Yates L, Robb S, Uyanik G, Mancini GM, Rees MI, Harvey RJ, Dobyns WB. TUBA1A mutations cause wide spectrum lissencephaly (smooth brain) and suggest that multiple neuronal migration pathways converge on alpha tubulins. Hum Mol Genet. 2010 Jul 15;19(14):2817-27. doi: 10.1093/hmg/ddq182. Epub 2010 May 12. (
  • NCBI Gene (
  • Tian G, Jaglin XH, Keays DA, Francis F, Chelly J, Cowan NJ. Disease-associated mutations in TUBA1A result in a spectrum of defects in the tubulin folding and heterodimer assembly pathway. Hum Mol Genet. 2010 Sep 15;19(18):3599-613. doi: 10.1093/hmg/ddq276. Epub 2010 Jul 5. (


The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? ( in the Handbook.

Reviewed: August 2013
Published: February 8, 2016