GTR Home > Conditions/Phenotypes > Chromosome 9q deletion syndrome

Disease characteristics

Excerpted from the GeneReview: Kleefstra Syndrome
Kleefstra syndrome is characterized by intellectual disability, childhood hypotonia, and distinctive facial features. The majority of individuals function in the moderate to severe spectrum of intellectual disability although a few individuals have mild delay and total IQ around 70. Although most have severe expressive speech delay with little speech development, general language development is usually at a higher level, making nonverbal communication possible. A complex pattern of other findings can also be observed including heart defects, renal/urologic defects, genital defects in males, severe respiratory infections, epilepsy/febrile seizures, autistic-like features in childhood, and extreme apathy or catatonic-like features after puberty.

Available tests

18 tests are in the database for this condition. Compare labs offering these tests.

Check Associated genes and Related conditions for additional relevant tests.

Associated genes

  • Also known as: RP11-188C12.1, EUHMTASE1, Eu-HMTase1, FP13812, GLP, GLP1, KMT1D, bA188C12.1, EHMT1
    Summary: euchromatic histone-lysine N-methyltransferase 1

Clinical features

  • Pyloric stenosis
  • Intellectual disability, severe
  • Irregular heart beat
  • Short stature
  • Apathy
  • Respiratory insufficiency
  • Vesicoureteral reflux
  • Thickened helices
  • Talipes equinovarus
  • Intellectual disability
  • Microcephaly
  • Flat face
  • Midface retrusion
  • Anteverted nares
  • Coarse facial features
  • Broad forehead
  • Cognitive impairment
  • Malar flattening
  • Ventricular septal defect
  • Downturned corners of mouth
  • Recurrent respiratory infections
  • Delayed eruption of teeth
  • Single transverse palmar crease
  • Seizures
  • Constipation
  • Obesity
  • Renal cyst
  • Synophrys
  • Cryptorchidism
  • Hypospadias
  • Micropenis
  • Renal insufficiency
  • Macroglossia
  • Everted lower lip vermilion
  • Brachycephaly
  • Mandibular prognathia
  • Hypertelorism
  • Facial asymmetry
  • Hearing impairment
  • Otitis media
  • Upslanted palpebral fissure
  • Natal tooth
  • Autism
  • Aggressive behavior
  • Obsessive-compulsive behavior
  • Stereotypic behavior
  • Delayed speech and language development
  • Muscular hypotonia
  • Limitation of joint mobility
  • Tetralogy of Fallot
  • Abnormality of the aortic valve
  • Abnormality of the aorta
  • Gastroesophageal reflux
  • Ventriculomegaly
  • Cerebral cortical atrophy
  • Neurological speech impairment
  • Sleep disturbance
  • Developmental regression
  • Highly arched eyebrow
  • Supernumerary nipples
  • Bowel incontinence
  • Scoliosis
  • Tracheobronchomalacia
  • Short nose
  • Abnormality of the pulmonary artery
  • Persistence of primary teeth
  • Aplasia/Hypoplasia of the corpus callosum
  • Tented upper lip vermilion
  • U-Shaped upper lip vermilion
  • Protruding tongue
  • Self-injurious behavior
  • Hernia
Show all (72)

IMPORTANT NOTE: NIH does not independently verify information submitted to the GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in the GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

Write to the Help Desk