When your child seems to be learning, developing, or growing slower than other children of the same age it can be worrisome and discouraging, or you may even deny there is anything wrong. Friends may even tell you, “Oh, Johnny didn’t talk until he was three either, and then once he did you couldn’t shut him up!” However, if you have nagging concerns about your child’s lack of speech, gross motor development, growth, floppiness or weakness, emotional development, or any gut feeling that something just is not right, you may just be a worried mother or your instincts may be correct.
The first step when you have any concerns is to take your child to the pediatrician. Ask for the pediatrician’s opinion about your child’s overall development, any physical or facial features that seem unusual (that may or may not be family traits). Also, any congenital (present at birth) defects of the heart, kidneys, or other organs should be detected and monitored closely.
If the pediatrician has determined that there may be some delay in cognitive or gross or fine motor development, such as reaching milestones later than expected, the next step is to ask the doctor to refer your child for baseline developmental testing. Developmental testing will give you an idea how your child is developing in relation to other children of the same age in speech (babbling, gesturing, or talking – appropriate ability to communicate for age), gross motor (crawling, walking), fine motor (finger feeding, grasping), and cognitive ability (such as understanding and following directions – “touch your belly button” “where’s your toy?”) This testing will give insight to your child’s strengths and weaknesses and whether the weaknesses are significant enough to warrant getting your child enrolled in speech, occupational, physical, or developmental therapy programs for extra help.
If the pediatrician determines that your child has significant delays in development or growth, and/or other issues such as unusual facial or physical features, birth defects, or signs of autism you will want to make sure that your child is referred to a medical geneticist, because many times, these symptoms can be attributed to an underlying genetic disorder.
When your child is scheduled to see the geneticist, it should be a complete and thorough evaluation. Before the visit, the office may retrieve any records they might need, such as other specialist consultation reports if your child has seen a cardiologist (heart) or nephrologist (kidney) or other specialists. This can also include paperwork you may need to fill out documenting your child’s family and personal medical history.
At the appointment, a genetic counselor will interview you in more depth about family history and create a pedigree, or family tree, to see if there are any patterns in the family medical history (if anything runs in the family) that are significant in making a diagnosis for your child. The next step is a complete physical evaluation of your child by the geneticist including vital signs (height, weight, head circumference, blood pressure, heart rate, etc.), examination of all body parts including genitalia (some syndromes include unusual features of genitalia), and review of systems (questions to help determine if all body systems are working normally). The geneticist may also have your child demonstrate different abilities such as running back and forth down a hallway, tandem walking forward (one foot in front of the other) and backward (one foot behind the other), and looking through a paper telescope to see which eye and hand are dominant, throwing and kicking to see which arm and leg are dominant, etc.
After all of these pieces are completed, the doctor will put everything together and discuss what his findings and recommendations are which may include testing.
Some genetic syndromes are considered to be only a “clinical” diagnosis. This means that there is no test available yet for these syndromes so the diagnosis is made based on the child’s collection of symptoms, facial features, or defects that are known to be associated with a certain syndrome.
Your child may have symptoms of a disorder which can be detected with genetic testing. In this case the geneticist may order specific blood tests such as a chromosome analysis, which can determine if your child’s karyotype is normal (46, XX if a girl or 46, XY if a boy) or if there is a basic chromsome disorder such as trisomy 21 (three #21 chromosomes – 47, XX or 47, XY) or Klinefelter syndrome (47, XXY – male with an extra female X chromosome) and FISH testing may be ordered which tests for small deletions or duplications of a specific a chomosome such as 22q11.2 deletion syndrome (velocardiofacial syndrome – a small deletion of the 22 chromosome), or molecular diagnostic testing which is even more in depth and determines such things as Prader-Willi syndrome or Angelman syndrome.
Your child may not fit a clinical diagnosis and may also have the battery of basic tests come out negative, so at this point you may agree to another blood test for chromosomal microarray analysis/comparative genomic hybridization. This one test is like approximately 2,000 tests rolled into one and it looks for microdeletions or microduplications in the chromosomal DNA.
Why is it important to know the name of your child’s underlying genetic disorder if he or she in fact has one?
Many genetic disorders are well known and if your doctor knows exactly what your child has, that knowledge may help determine the best possible care for your child.
Did you know that children with Down syndrome are susceptible to having heart and thyroid issues and should be followed on a regular basis for these? Did you know that when they are of an age to play sports they should have an x-ray of the cervical spine because they are more likely to have unstable neck vertebrae? If your child with Down syndrome is not followed by a geneticist, you may not know this.
Many genetic syndromes have their own specific issues like this to watch for, so if you know what your child has, you will have more guidance about what to expect as your child grows.
Another reason to know is for future family planning for you or your children, and to know the chances of the same genetic disorder happening again in the family. Some syndromes are passed down on the autosomal chromsomes (the 44 chromosomes that do not determine the sex of the child), some are passed down on the X chromsome (these disorders are called X-linked or sex-linked), and some are just “de novo”, or flukes! The flukes are abnormalities that happened either when the sperm or the egg were developing or shortly after conception when the embryo was beginning to form, during the first cell divisions. These de novo disorders are unlikely to happen again if the parents have more children or when siblings have children. However, the affected child can pass down their own genetic makeup.
Sometimes even the most in depth testing will still not reveal any answers and this may be frustrating, but remember, we do not yet have the ability to test for everything that may exist. No matter what the outcome, the important things to remember are to love and enjoy your child, see that he receives regular follow-up for any medical conditions, and identify his strengths and weaknesses and give him every opportunity to learn and reach his full potential.
(Sarah J Tyler has worked as a clinic coordinator for a hospital genetics program and she is the mom of a child with a chromosome disorder.)
