Introduction

Ellis-van Creveld (EVC) syndrome, also known as chondroectodermal dysplasia, is a rare genetic condition that affects the bones, causing skeletal dysplasia, and can affect the teeth, hair, and nails, which may be dysplastic. Additionally, it can sometimes involve the heart, leading to congenital cardiac defects.¹ Children with this condition may be shorter than average because of short limbs, may have extra fingers or toes, known as postaxial polydactyly, and some may be born with heart problems caused by a congenital heart defect and short ribs.1 Because of its genetic heterogeneity, variable clinical signs, and impact on family planning, genetic counselling is an essential component of care for affected families.

Why does it happen?

EVC syndrome is caused by the mutation (change) of two major genes called the EVC gene and the EVC2 gene, although other genes have also been implicated in recent studies.² EVC syndrome is usually passed down in families through an autosomal recessive pattern. This means that both parents carry one copy of the mutated gene but usually do not have any health problems themselves. When both parents are carriers:³ 

• Each pregnancy has a 25% chance (1 in 4) of the child having EVC syndrome
• A 50% chance (1 in 2) that the child will be a healthy carrier like the parents
• A 25% chance (1 in 4) that the child will not carry the gene at all

In some cases, EVC can be inherited through different patterns, and although rare, individuals may inherit it in an autosomal dominant pattern.¹ 

How can it be detected early?

• During pregnancy, an ultrasound may show signs such as short arms and legs, extra fingers, or a small chest. Sometimes heart problems can also be seen³
• Genetic testing: If ultrasound findings suggest EVC, a blood test on the parents or a sample from the baby (before or after birth) can check for changes in the EVC genes
• Future pregnancies: If the exact gene change is known in the family, parents can choose tests during pregnancy (chorionic villus sampling or amniocentesis) or even preimplantation genetic testing (PGT) before pregnancy using IVF

What does genetic counselling involve?

Genetic counselling is an important part of care for families living with EVC. It involves:^{4 5}

• Prognosis (health outlook): Counsellors explain that children with Ellis-van Creveld syndrome may live a healthy life if heart problems are mild or corrected, but some may face serious complications if heart defects or breathing problems are severe. They also note that the degree of physical differences, like short stature or extra fingers, can vary widely, even between siblings. This helps families form realistic expectations about health, development, and quality of life. Counsellors also help families understand that symptoms can be different even between siblings. Some children may have mild health issues, while others may have more serious heart or breathing problems.

A recent review suggests that certain variants are more frequently associated with severe manifestations such as complex congenital heart disease or lethal thoracic hypoplasia.

• The chance of the condition happening again: Families are informed about the 25% recurrence risk in every pregnancy if both parents are carriers. Counsellors may use charts, drawings, called a pedigree, or simple numbers to make this clear. If the syndrome has been diagnosed in one child, this information is crucial for future family planning⁶
• Tests available before and during pregnancy: Parents receive information about prenatal tests, such as chorionic villus sampling or amniocentesis, to detect the syndrome during pregnancy, and preimplantation genetic testing (PGT) if they choose in vitro fertilisation. These options allow families to make decisions early, based on their medical, ethical, or religious values
• Options for family planning and support for decision-making: Counselling is not only about risks but also about providing support for families’ next steps. Counsellors help them consider options such as preparing for the birth of a child with special needs, seeking specialised care (cardiology, orthopaedics, dentistry). Emotional support and referrals to patient communities are also part of this guidance
• Emotional and cultural aspects: In some regions, EVC is more common in families where parents are related, such as cousins. Counselling is especially important in these situations. Families may face difficult choices when prenatal testing shows severe problems. Genetic counsellors can provide medical information and emotional support, while respecting family values, religion, and culture⁵
• Challenges: EVC raises some challenges during genetic counselling, such as difficulty in explaining the inheritance patterns, limited treatment options, and limited access to testing and specialised care. Genetic testing for EVC may not be available everywhere. Therefore, families in low-resource regions may face barriers in confirming the diagnosis or accessing genetic counselling

Strategies to address these include using visual aids, providing consultations, connecting families with patient advocacy organisations, and ensuring culturally sensitive counselling methods.

A leaflet that the patient can use to better understand EVC (prepared by the writer)

Summary

Genetic counselling gives families the knowledge they need to understand Ellis-van Creveld syndrome, make informed decisions, and plan for the future. With advances in genetic testing, counsellors are now better equipped to provide families with personalised information about prognosis and reproductive options.

FAQs

Is ellis-van creveld syndrome the same as dwarfism?

Ellis-van Creveld syndrome is an inherited disorder of bone growth that results in very short stature (dwarfism). People with this condition have particularly short forearms and lower legs and a narrow chest with short ribs.

What is the life expectancy of ellis-van creveld syndrome?

Nearly 50% of patients die by 18 months of age from cardiopulmonary complications. Motor development and intelligence are usually normal. This condition is caused by variants in several t genes, including EVC1 and EVC2, and occasionally in the DYNC2LI1, DYNC2H1, GLI1, WDR35, PRKACA, PRKACB, and SMO.

What is the difference between dysplasia and dwarfism?

In skeletal dysplasias, like dwarfism, a child's bones do not grow in the usual way. Often, children with skeletal dysplasias are much shorter than average, or their bones may be more fragile than is typical. Dwarfism is a type of short stature that happens when a child's bones cannot grow to a typical length.