Niikawa-Kuroki syndrome

=Niikawa-Kuroki Syndrome = Niikawa-Kuroki Syndrome, also known as Kabuki syndrome, is a rare genetic disorder characterized by distinctive facial features, growth delays, intellectual disabilities, and skeletal abnormalities. It was first described in 1981 by Japanese researchers Niikawa and Kuroki.

Clinical Features

Individuals with Niikawa-Kuroki Syndrome typically present with a range of clinical features, including:

• Facial Dysmorphism: The facial features often include long palpebral fissures, arched eyebrows, a depressed nasal tip, and large, prominent ears.
• Growth Delays: Affected individuals may experience postnatal growth retardation, leading to short stature.
• Intellectual Disability: The degree of intellectual disability can vary, but most individuals have mild to moderate cognitive impairment.
• Skeletal Abnormalities: These may include scoliosis, brachydactyly, and joint laxity.
• Other Features: Additional features can include congenital heart defects, renal anomalies, and immune system dysfunction.

Genetics

Niikawa-Kuroki Syndrome is primarily caused by mutations in the KMT2D gene, which is located on chromosome 12. This gene is responsible for encoding a histone methyltransferase, which plays a crucial role in chromatin modification and gene expression. In some cases, mutations in the KDM6A gene, located on the X chromosome, have also been implicated. This gene encodes a histone demethylase, which is involved in the regulation of gene expression.

Diagnosis

Diagnosis of Niikawa-Kuroki Syndrome is based on clinical evaluation and the identification of characteristic features. Genetic testing can confirm the diagnosis by identifying mutations in the KMT2D or KDM6A genes.

Management

Management of Niikawa-Kuroki Syndrome is symptomatic and supportive. It may involve:

• Early Intervention: Early developmental intervention and special education programs can help maximize the potential of affected individuals.
• Medical Management: Regular monitoring and treatment of associated medical conditions, such as heart defects and immune dysfunction, are essential.
• Genetic Counseling: Families may benefit from genetic counseling to understand the inheritance pattern and recurrence risks.

Epidemiology

Niikawa-Kuroki Syndrome is a rare condition, with an estimated prevalence of 1 in 32,000 to 1 in 86,000 individuals. It affects both males and females equally.

History

The syndrome was first described in 1981 by Dr. Norio Niikawa and Dr. Yoshikazu Kuroki, who independently reported cases of children with similar clinical features in Japan.

See Also

• Rare diseases
• Genetic disorders
• Developmental disorders
• Niikawa, N., et al. (1981). "Kabuki make-up syndrome: A syndrome of mental retardation, unusual facies, large and protruding ears, and postnatal growth deficiency." Journal of Pediatrics.
• Kuroki, Y., et al. (1981). "A new malformation syndrome of long palpebral fissures, large ears, depressed nasal tip, and skeletal anomalies associated with postnatal dwarfism and mental retardation." Journal of Pediatrics.

NIH genetic and rare disease info

• NIH info on Niikawa-Kuroki syndrome

Niikawa-Kuroki syndrome is a rare disease.