The new genetic disorder every mom needs to know about

From the first time Dr. Sheila Kambin laid eyes on her newborn son Aidan, she knew something wasn’t right.

Aidan had a sacral pit—a dimple on his lower back—and low set ears. He was full term but weighed just 5 pounds and was sent to a neonatal intensive-care unit (NICU) where he was evaluated for low platelet count, low blood sugar, problems with temperature regulation and feeding.

“He was never able to latch, but I never knew why,” she said.

At just 4 months old, Aidan had surgery to repair an inguinal hernia, a bulge in the abdominal muscles. He also had ligament laxity (loose ligaments), hammer toes, distinct facial features, long tapered fingers, and the uvula in the back of his throat was split into two. Kambin later learned Aidan had a submucous cleft palate, or a cleft palate covered by a membrane, the reason for his feeding troubles.

Perhaps one of the most concerning symptoms to Kambin was that Aidan wasn’t reaching his developmental milestones.

“We started to notice he was delayed by about 6 months on every single one of them,” she said.

His preschool teacher was also concerned.

“His teacher said, ‘I’ve been teaching preschool for 30 years and I’m not sure what exactly is wrong with Aidan but something is wrong with him.’”

Kambin brought Aidan to 27 clinical specialists and 2 geneticists but no one could give them a diagnosis. Finally, after seeing a developmental pediatrician and 14 additional specialists over six months, they finally had a diagnosis: 22q11.2 deletion syndrome, a serious, potentially fatal condition that experts say more kids are being diagnosed with than ever before.

What is 22q11.2 deletion syndrome?
22q11.2 deletion syndrome, also known as DiGeorge syndrome (DGS) or velo-cardio-facial syndrome (VCFS), is a genetic disorder that affects about 1 in 2,000 people.

It’s the most common deletion syndrome, meaning there is a missing section from one of the 46 chromosomes that make up our DNA. Unlike conditions like Turner Syndrome, where a whole chromosome is missing, or Down Syndrome, where there’s an extra copy, 22q11.2  occurs when there is a missing section, or microdeletion of a chromosome.  In this case, it’s chromosome 22.

22q11.2  deletion syndrome can affect anybody, regardless of race or ethnicity and is not affected by a mother’s age. In about 20 percent of people, it’s inherited, so a child has a 50/50 chance of having it if one of their parents does as well.

Plus, unlike other genetic conditions that are more likely to be passed onto a baby if both parents are carriers of a gene mutation, only one parent has to be missing a section of the chromosome.

According to a recent study in the journal Prenatal Diagnosis, of the 24 babies who were diagnosed with 22q11.2  deletion syndrome in utero, 15 were inherited, 6 were not inherited, and 3 were unknown.

What are the signs and symptoms?
There are over 200 different symptoms that range from mild to severe.  On average, each person will have 10.
According to a study in GeneReviews, 74 percent of people will have congenital heart disease which includes several heart problems that can be mild, or life threatening in newborns and require surgery.

“Most children with 22q11.2 deletion syndrome will sail through the neonatal period without any big problems but a small fraction of them are going to have serious congenital heart disease that needs attention right away,” according to Dr. Robert Marion, chief of the division of genetics in the department of pediatrics at Albert Einstein College of Medicine and The Children’s Hospital at Montefiore in New York City.
Another common condition is hypocalcemia, or low calcium levels that can cause seizures and long-term health problems. In fact, a study in the journal Genetics in Medicine found that newborns with hypocalcemia and seizures were more likely to have severe intellectual disabilities as adults.

Other common conditions include immune deficiency and developmental problems like learning disabilities, intellectual disabilities, ADHD and autism.

“We know there are some single gene disorders or microdeletion syndromes that predispose to autism and 22q11.2 is one of them,” Marion said.

About a third of children will also develop mental illnesses like schizophrenia, bipolar disorder, anxiety and depression later on in life.

Many people have it, but don’t even know it.
As more people are now being diagnosed, experts say it’s likely that the number of people who have it will be even more than they previously believed.

Plus, unlike Down syndrome and cystic fibrosis, most women are not routinely screened for 22q11.2 during pregnancy despite the fact that it’s more common, according to Dr. Sue Gross, a professor of women's heath, pediatrics and genetics at The Albert Einstein College of Medicine in New York City and chief medical officer of Natera.

Another factor that may cause a delay or missed diagnosis is that not only do symptoms vary from person to person, but may be labeled as something else. So, a child with a healthy heart could be diagnosed with a learning disability, without ever knowing he has 22q11.2. The longer the delay in diagnosis, the more vulnerable kids can be to life-threatening medical conditions, developmental delays, and problems in school.

Experts say many times when children are evaluated for the disorder, both child and parent are diagnosed.

“There are people with this condition that go undetected probably most of their lives,” Marion said.

What you should know.
A non-invasive prenatal test (NIPT) or cell-free DNA test is a simple blood test that can  screen for 22q11.2  deletion syndrome in the first trimester. All of the tests look at the total of the mother’s DNA and placental DNA. Natera’s Panorama is the only test that separates the two so the amount of false negatives and false positives are lower.

Yet all of these tests are only screening tools and a diagnosis should be confirmed with amniocentesis or chorionic villus sampling (CVS).

Today, Kambin’s son Aidan is 10 years old, attends a school for children with learning differences, and is thriving.

“He has a lot of friends and he’s a very happy kid,” according to Kambin who is also the board chairman of the International 22q11.2 Foundation.

“I obsess about his future but then I remind myself that I don’t know what the future is for his sister who doesn’t have it,” she said. “No one knows the outcome. All we can do is make sure the environment is as supportive as possible.”