The RTL1 gene helps the placenta support a growing baby during pregnancy. If it does not work properly, growth before birth and early development can be affected. This gene plays an important role in a region of chromosome 14 where the body mainly uses the copy inherited from one parent. Too little or too much RTL1 activity is linked to rare conditions including Temple syndrome and Kagami-Ogata syndrome.
What is a gene?
A gene is a stretch of DNA that carries instructions your cells use to make molecules or regulate processes in the body. Some genes provide the information needed to produce proteins, the parts of cells that do the work. Other genes mainly help control when certain processes happen, where they happen, and how strongly they operate. Together, genes affect how the body develops and works, and they can shape how you respond to food, stress, or medications. For a more detailed look at this topic, you can learn more in the LearnHub.
Overview
RTL1Gene function
What if the gene works
The RTL1 gene is mainly active in the placenta during pregnancy. It helps the placenta develop and supports the exchange of oxygen and nutrients between parent and baby. This activity supports normal fetal growth.
Risk
What if the gene does not work
Changes that lower or raise activity of the RTL1 gene can contribute to chromosome 14q32 imprinting conditions. Reduced activity is linked to Temple syndrome, while excess activity is linked to Kagami-Ogata syndrome; milder or more severe changes can affect timing and severity.
Treatment
What does that mean for your treatment
No treatment or management approach specifically tied to pathogenic or loss-of-function variants in the RTL1 gene is currently established. The RTL1 gene is being studied mainly as a biomarker and possible growth driver in some cancers, but this has not led to routine treatment choices.
Conditions associated with RTL1
Gene function
What if the gene works
During pregnancy, the placenta needs a steady blood supply to move oxygen and nutrients to the developing baby. When the RTL1 gene is working normally, it helps the placenta build and maintain this support system, especially on the baby's side. Its activity is centered mainly in placental tissue and supports healthy growth during pregnancy.
The RTL1 gene supports the development of placental tissue during pregnancy. This helps the placenta form the structures needed to support the baby's growth.
One of the RTL1 gene's main roles is to help maintain the tiny blood vessels on the baby's side of the placenta. These vessels help oxygen and nutrients move efficiently between parent and baby.
What is a variant?
A genetic variant is a small difference in the DNA sequence within a gene. These differences are common and help shape normal human diversity, including differences in appearance, metabolism, or how the body responds to environmental influences. Many variants do not cause any noticeable effect and simply reflect natural genetic variation. In some cases, though, a variant can change a gene’s function more substantially and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the RTL1 gene often change dosage, so cells make too much or too little RTL1 protein, rather than altering the protein itself. Because only one parental copy is usually active, changes in the gene or nearby control regions can strongly affect RTL1 gene function. Milder variants may partly shift activity, while more severe variants can greatly disrupt expression and are linked to earlier or more noticeable features in chromosome 14 imprinting conditions.
How variants are linked to conditions
RTL1 gene variants do not yet have a broadly confirmed link to a specific health condition, though this can change as research develops. If you have a confirmed finding in the RTL1 gene, your doctor or genetic counselor can explain what it may mean in the context of your personal and family history.
A variant is not necessarily a diagnosis
Genetic variants are a usual part of human biology and are widely present in the general population. Most do not have a direct impact on health and simply contribute to natural human diversity. For many genes, carrying a variant associated with a condition indicates a possible link rather than a definite diagnosis, especially when several genes and environmental factors are involved. In some situations, though, a single well-characterized variant in a particular gene is enough to confirm a diagnosis.
Are there things that can increase or change my risk?
There isn't yet broadly confirmed evidence on specific factors that increase or reduce health risk related to the RTL1 gene itself. Risk is more closely tied to the specific genetic change and how this region is inherited than to lifestyle or everyday exposures.
Inheritance of RTL1 variants
The RTL1 inheritance pattern is unusual because this gene is imprinted, which means the effect depends on which parent a changed copy comes from. In RTL1-related conditions, the father’s copy is the active one, so a variant or chromosome change involving the paternal copy is the one most likely to affect health. The same change inherited from the mother may have little or no effect because the maternal RTL1 copy is normally switched off. RTL1 is on chromosome 14, so it is not X linked or Y linked, but parent of origin matters.
What does my RTL1 result mean for my family?
There is not yet a broadly confirmed Mendelian inheritance pattern for RTL1 that neatly predicts what a result means for relatives, because its health effects are closely tied to parent-of-origin and other changes in the same chromosome region. If you have a specific RTL1 result and questions about what it could mean for your family, a doctor or genetic counselor can explain the family implications in the context of that exact finding.
Genetic information
Genetic testing
How you find out about variants
RTL1 genetic testing usually uses a blood or saliva sample. To find out about RTL1 variants, a lab may combine DNA sequencing with copy number and methylation testing, which checks for gene changes, extra or missing DNA, and altered chemical tags that control whether the maternal or paternal copy is active.
When should I consider getting a genetic test?
There isn't yet a broadly established, RTL1-specific reason for genetic testing on its own. Testing choices are usually based on someone’s symptoms, growth or developmental concerns, and family history, together with a doctor or genetic counselor.
A genetic result is only one part of your health story
Genetic results can provide useful insight, but how much they explain depends on the condition and on the type of variant involved. Over time, many factors also shape how the body functions, including lifestyle, environment, age, and medical history. In some conditions, especially those influenced by many genes, genetic information offers context rather than certainty and is best interpreted alongside other parts of care. In other situations, a genetic result may give a clear answer. In areas like medication response, genetic results can also help put individual experiences into context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. Small differences in genes can change how the body breaks down a drug, moves it into tissues, or responds to it at its target. That helps explain why the same treatment may work well for one person, have less effect in another, or cause more side effects in someone who is more sensitive.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic differences affect the way medications work. It looks at gene and drug patterns to help explain why the same treatment can work differently from one person to another. For many medicines, genes influence both how strongly a drug acts and how the body handles it. This information can support treatment decisions that are better informed and more individualized. If you want to learn more about this topic, you can read more in the LearnHub.
Drugs influenced by the RTL1 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in predicting how medicines will work or which side effects are more likely, so general concerns about your health, symptoms, or any new or changing medicines are best discussed with your doctor or pharmacist.
History
RTL1 entered genetics research as scientists mapped the imprinted region on chromosome 14, where some genes are active mainly from one parent’s copy. In the early 2000s, researchers recognized RTL1 as an unusual gene with similarities to an ancient retrotransposon, a stretch of DNA left behind by long-ago viral-like elements. That finding drew attention because it showed how older pieces of DNA could become part of normal human biology. From these first observations, research expanded steadily. Studies in mice and humans then placed RTL1 within the broader story of genomic imprinting, helping shape modern understanding of parent-of-origin effects in development and pregnancy-related conditions.