Trigger Warning

The following piece deals with incest and is not suitable for all readers.

So far in this series on incest, we have covered how society looks at incest and how it is unacceptable, even in today’s society. We have also visited how incest is reinforced by the predator through grooming and tricking the victim through intermittent favorable treatment to keep them from telling or ending the abuse.

This article will examine the genetic consequences of incest on child victims.

Types of Incest

Although, when we think of incest, many of us might think of father/daughter abuse, there are many other forms incest can take.

Did you know that incest between mother/son can include the son as the perpetrator? There are rare instances of sons who are adolescents or young adults sexually assaulting their mothers. In these cases, incest is often forced.

Sibling/sibling incest occurring during childhood is considered typical but is rarely reported. Such behavior is considered child-on-child sexual abuse if it occurs without consent, by coercion, or without equality between the two kids. The most commonly reported form of sibling/sibling incest is the abuse of a younger sibling by an older one. Sibling abusive incest is more likely in families where one or both parents are absent or emotionally unavailable. The absence of the father in the home is found to be a significant part of most cases of sexual abuse of female children by their brothers.

Consensual sex between two adult family members is illegal in most states and countries worldwide. Indeed, the Convention on Human Rights states that all familial sex is criminal even if both parties give full consent and know the consequences of their actions.

Stranger Danger

Growing up, we were taught never to talk to strangers. This rule existed because of the danger strangers can wreak on children. Now we teach children to yell “stranger!” and run away; that is good advice for any child living in today’s world.

However, research has shown that 10-20% of children who live through incest become victims of rape by a family member (Langan and Harlow, 1994). Most rape victims in the United States are traumatized before the age of eighteen, and 29% of those rapes occur before eleven.

Of child rape victims, 11% are abused by their genetic fathers, and 16% are raped by other relatives. There are no statistics on how many women commit incest with their children.

Incest between a father and son is under-reported, and the prevalence of incest between a parent and their child is difficult to estimate because of the secrecy

Boys who adult family members molest have solid psychological responses such as denial, anxiety, dissociation, and self-mutilation. Common coping strategies might include becoming an angry avenger, a passive victim, a rescuer, a daredevil, or conforming to the misbehavior of the adult.

Worse than the behaviors of a male or female survivor of childhood incest listed above, victims of incest may plan and execute, dying by suicide.

Obviously, very young children cannot get pregnant by encounters with a male relative, but the tremendous costs paid by the child emotionally, physically, and genetically are tremendous.

The Genetic Costs of Incest

Sex between two close family members that results in pregnancy the consequences to the baby are tremendous. While genetic changes that are consequential usually take a few generations of incestuous behavior to show up in a family, there can be instant consequences for a child born to family members.

Incest is harmful in many ways, including genetically. When two closely related people have sex, and the female becomes pregnant, there is an increased risk of recessive gene disorders.

The reason involves how genes are passed from parent to child. Children receive one copy of a gene from each parent. Usually, the genes for the formation of things like autoimmune systems are inherited from each parent, with the harmful genetic material being overridden by the dominant material. The result is a healthy individual who harbors a recessive genetic mistake.

When related individuals get pregnant, they decrease genetic variations, and the recessive gene they have may combine to become dominant in their child, causing many types of congenital disabilities.

Below find a list of some of the birth defects caused by incest. Please note that not all the variations cause severe problems for the children of incest, but many do.

Lower IQ Scores. Inbreeding can negatively affect the child’s intellectual abilities, even in some cases causing developmental disorders.

Blue Eyes. While inheriting blue eyes from each parent’s recessive gene is harmless, it can also be caused by incest.

Cystic Fibrosis. Cystic fibrosis is a severe disease that affects the cells that produce mucus, sweat, and digestive juices. The disorder causes these fluids to become thick and sticky, plugging up tubes, ducts, and passageways.

Premature Birth. Children of incest are in danger of premature birth and being underweight and undersized. Viable babies of incestuous couples are also likely to have physical deformities.

Cleft Palate. A cleft palate is a common congenital disability that genetic abnormalities in both parents can cause. Children with cleft palates have difficulties speaking and feeding.

Heart Conditions. The birth of a baby with a deformed or other malfunctioning heart is one consequence of incest. Unfortunately, if they survive, these children will have shorter lives filled with endless cardiac problems.

Neonatal Mortality. The recessive genes inherited by the children of close relatives sometimes lead to a baby not living past gestation or dying soon after birth.

Not all genetic changes caused by incest are lethal, but many cause lifelong problems that could have been avoided.

Ending Our Time Together

It is vital to understand the consequences of incest because the results, not only genetic but emotionally, are tremendous.

When we think of a child molester, we think of the stranger lurking in the bushes or bathrooms at playgrounds. Rarely do we automatically consider that children are molested by their parent or someone else closely related to the child.

Sex between unrelated individuals rarely results in genetic defects. However, incest, especially when it is not between consenting adults, is a crime that causes heartache in so many forms.

Genetic disorders born from incest can be benign and may not raise their ugly head for several generations; all too often, congenital disabilities are either highly detrimental to the child or cause their death.

We must work as a society to shine a bright light on incest and child abuse of any type to give our children a brighter and safer future. Our species depends on it, and it is the morally right thing to do.

End child abuse now.

“Childhood should be carefree, playing in the sun, not living a nightmare in the darkness of the soul.” Dave Pelzer

“Betrayal is too kind a word to describe a situation in which a father says he loves his daughter but claims he must teach her about the horrors of the world to make her a stronger person; a situation in which he watches or participates in rituals that make her feel like she is going to die. She experiences pain that is so intense that she cannot think; her head spins so fast she can’t remember who she is or how she got there.” Margaret Smith


Incest”Oxford University Press. 2013. Retrieved August 27, 2013.

Incest. Retrieved from:

Langan, P. A., & Harlow, C. W. (1994). Child rape victims, 1992. US Department of Justice, Office of Justice Programs, Bureau of Justice Statistics.

Schneider, D. M. (1976). “The meaning of incest.” The Journal of the Polynesian Society. 85 (2): 149–169.


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The Healing Book Club


The Healing Book Club, led by Sabra Cain, meets weekly to discuss a book about mental health issues. The current book that the club is reading is called Daring Greatly, written by Brene’ Brown, Ph.D. MSW.

Below is a brief look at the book.

Every day we experience the uncertainty, risks, and emotional exposure that define what it means to be vulnerable or to dare greatly. Based on twelve years of pioneering research, Brené Brown, Ph.D., MSW, dispels the cultural myth that vulnerability is weakness and argues that it is, in truth, our most accurate measure of courage.

Brown explains how vulnerability is both the core of difficult emotions like fear, grief, and disappointment and the birthplace of love, belonging, joy, empathy, innovation, and creativity. She writes: “When we shut ourselves off from vulnerability, we distance ourselves from the experiences that bring purpose and meaning to our lives.”

Daring Greatly is not about winning or losing. It’s about courage.



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Mindfulness, Prayer, and Meditation Circle


Meditation can be an integral part of healing from trauma. Our 9-week self-study video course helps you integrate this fantastic method of grounding, centering, and focus. Join the Mindfulness, Prayer, and Meditation Circle today!

Incest the Taboo Subject

Trauma Bonding and Incest