What are the signs and symptoms of FG syndrome? The Human Phenotype Ontology provides the following list of signs and symptoms for FG syndrome. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Aplasia/Hypoplasia of the corpus callosum 90% Behavioral abnormality 90% Broad forehead 90% Cognitive impairment 90% High forehead 90% Low-set, posteriorly rotated ears 90% Muscular hypotonia 90% Abnormality of the palate 50% Brachydactyly syndrome 50% Clinodactyly of the 5th finger 50% Cryptorchidism 50% EEG abnormality 50% Epicanthus 50% Fine hair 50% Mask-like facies 50% Open mouth 50% Seizures 50% Strabismus 50% Abnormality of the intestine 7.5% Hernia of the abdominal wall 7.5% Hypertonia 7.5% Ptosis 7.5% Single transverse palmar crease 7.5% Sensorineural hearing impairment 4/6 Feeding difficulties in infancy 5/8 Seizures 5/8 Prominent forehead 3/8 Scoliosis 2/8 Abnormal heart morphology - Abnormality of the nasopharynx - Abnormality of the sternum - Anal atresia - Anal stenosis - Anteriorly placed anus - Attention deficit hyperactivity disorder - Broad hallux - Broad thumb - Camptodactyly - Choanal atresia - Cleft palate - Cleft upper lip - Clinodactyly - Constipation - Delayed closure of the anterior fontanelle - Delayed speech and language development - Dental crowding - Facial wrinkling - Frontal bossing - Frontal upsweep of hair - Heterotopia - High pitched voice - Hydrocephalus - Hypertelorism - Hypospadias - Inguinal hernia - Intellectual disability - Intestinal malrotation - Joint contracture of the hand - Joint swelling onset late infancy - Large forehead - Long philtrum - Lumbar hyperlordosis - Microtia, first degree - Motor delay - Multiple joint contractures - Narrow palate - Neonatal hypotonia - Partial agenesis of the corpus callosum - Plagiocephaly - Postnatal macrocephaly - Prominent fingertip pads - Prominent nose - Pyloric stenosis - Radial deviation of finger - Sacral dimple - Short neck - Short stature - Skin tags - Sparse hair - Split hand - Syndactyly - Thick lower lip vermilion - Umbilical hernia - Underdeveloped superior crus of antihelix - Wide anterior fontanel - Wide mouth - Wide nasal bridge - X-linked inheritance - X-linked recessive inheritance - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.