About Down Syndrome - National Human Genome Research …
2017年6月29日 · Down syndrome is a chromosomal condition related to chromosome 21. It affects 1 in 800 to 1 in 1000 live born infants. What are the symptoms of Down syndrome? People who have Down syndrome have learning difficulties, mental disability, a characteristic facial appearance, and poor muscle tone (hypotonia) in infancy.
Down Syndrome - StatPearls - NCBI Bookshelf - National Center …
2023年8月8日 · Down syndrome (trisomy 21) is a genetic disorder caused by the presence of all or a portion of a third chromosome 21. Patients typically present with mild to moderate intellectual disability, growth retardation, and characteristic facial features.
Down syndrome - Symptoms and causes - Mayo Clinic
2024年11月12日 · Down syndrome is a genetic condition caused when an unusual cell division results in an extra full or partial copy of chromosome 21. This extra genetic material causes the developmental changes and physical features of Down syndrome.
Genetics of Down syndrome - Wikipedia
Down syndrome is a chromosomal abnormality characterized by the presence of an extra copy of genetic material on chromosome 21, either in whole (trisomy 21) or part (such as due to translocations).
Down syndrome: MedlinePlus Genetics
Down syndrome is a chromosomal condition that is associated with intellectual disability, a characteristic facial appearance, and weak muscle tone (hypotonia) in infancy. Explore symptoms, inheritance, genetics of this condition.
Down Syndrome | Birth Defects | CDC - Centers for Disease …
2024年12月26日 · Down syndrome is a genetic condition where a person is born with an extra chromosome. This can affect how their brain and body develop. People diagnosed with Down syndrome can lead healthy lives with supportive care.
Down syndrome - Wikipedia
Down syndrome or Down's syndrome, [12] also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. [3] It is usually associated with developmental delays, mild to moderate intellectual disability , …
Down Syndrome (Trisomy 21) - National Human Genome …
3 天之前 · Down syndrome (also called Trisomy 21) is a genetic condition caused by an error in the process that replicates and then divides up the pairs of chromosomes during cell division, resulting in the inheritance of an extra full or partial copy of chromosome 21 from a parent.
Down syndrome - PMC
Down syndrome (DS) is the most common genomic disorder of intellectual disability and is caused by trisomy of Homo sapiens chromosome 21 (HSA21). The eponym of the syndrome is from Down, who described the clinical aspects of the syndrome in 1866 (REF. 1).
Down Syndrome (Trisomy 21) - Down Syndrome (Trisomy 21)
Down syndrome is an abnormality of chromosome 21 that can cause intellectual disability, microcephaly, short stature, and characteristic facies. Diagnosis is suggested by physical anomalies and abnormal development and confirmed by cytogenetic analysis. Management depends on specific manifestations and anomalies.