|http://ghr.nlm.nih.gov/ A service of the U.S. National Library of Medicine®|
The official name of this gene is “TGFB-induced factor homeobox 1.”
TGIF1 is the gene's official symbol. The TGIF1 gene is also known by other names, listed below.
The TGIF1 gene provides instructions for making a protein called TG-interacting factor. This protein is important for normal development of the front part of the brain (forebrain). TG-interacting factor is a transcription factor, which means that it regulates the activity of certain genes. This protein turns off genes by attaching (binding) to specific regions of DNA or by interacting with other DNA-binding proteins.
TG-interacting factor regulates signaling pathways that are important for embryonic development. This protein blocks the signals of the transforming growth factor beta (TGF-β) pathway. This signaling pathway transmits chemical signals from the cell surface to the nucleus, which allows the environment outside the cell to affect how the cell produces other proteins. TG-interacting factor also blocks a molecule called retinoic acid from regulating gene activity. Retinoic acid, a form of vitamin A, binds to a group of transcription factors that regulate a number of genes important for early development. By blocking these signaling pathways, TG-interacting factor ensures that certain genes are turned off at the proper time.
The TGIF1 gene belongs to a family of genes called homeobox (homeoboxes).
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? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genefamilies) in the Handbook.
At least 13 mutations in the TGIF1 gene have been found to cause nonsyndromic holoprosencephaly. This condition occurs when the brain fails to divide into two halves (hemispheres) during early development. TGIF1 gene mutations are the fourth most common cause of nonsyndromic holoprosencephaly. These mutations disrupt the protein's ability to bind with DNA or interact with other proteins. As a result, TG-interacting factor cannot block the signals of the TGF-β pathway and retinoic acid. If the signals involved in forebrain development are not properly regulated, the brain does not separate into two hemispheres. The signs and symptoms of nonsyndromic holoprosencephaly are caused by abnormal development of the brain and face.
Cytogenetic Location: 18p11.3
Molecular Location on chromosome 18: base pairs 3,411,926 to 3,458,410
The TGIF1 gene is located on the short (p) arm of chromosome 18 at position 11.3.
More precisely, the TGIF1 gene is located from base pair 3,411,926 to base pair 3,458,410 on chromosome 18.
See How do geneticists indicate the location of a gene? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genelocation) in the Handbook.
You and your healthcare professional may find the following resources about TGIF1 helpful.
You may also be interested in these resources, which are designed for genetics professionals and researchers.
See How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/naming) in the Handbook.
cell ; DNA ; embryonic ; gene ; growth factor ; holoprosencephaly ; homeobox ; molecule ; nucleus ; protein ; transcription ; transcription factor
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
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? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.