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The following is a list of genetic disorders and if known, type of mutation and for the chromosome involved. Although the parlance "disease-causing gene" is common, it is the occurrence of an abnormality in the parents that causes the impairment to develop within the child. There are over 6,000 known genetic disorders in humans.
A karyotype of an individual with trisomy 21, showing three copies of chromosome 21. An abnormal number of chromosomes is known as aneuploidy, and occurs when an individual is either missing a chromosome from a pair (resulting in monosomy) or has more than two chromosomes of a pair (trisomy, tetrasomy, etc.).
Down syndrome is the most common chromosomal abnormality, [26] occurring in about 1 in 1,000 babies born worldwide, [1] and one in 700 in the US. [18] In 2015, there were 5.4 million people with Down syndrome globally, of whom 27,000 died, down from 43,000 deaths in 1990.
Trisomy 18 is a chromosomal abnormality characterized by the presence of an extra copy of genetic material on the 18th chromosome, either in whole (trisomy 18) or in part (such as due to translocations). The additional chromosome usually occurs before conception. The effects of the extra copy vary greatly, depending on the extent of the extra ...
Complete trisomy 8 causes severe abnormalities in the developing fetus and can be a cause of miscarriage. [2] [3] Complete trisomy 8 is usually a gestational lethal condition, whereas trisomy 8 mosaicism is less severe and individuals with a low proportion of affected cells may exhibit a comparatively mild range of physical abnormalities and developmental delay. [4]
Many individuals may exhibit EEG, CT, or MRI abnormalities. Hyporeflexia, gait abnormalities, and truncal or symmetric limb hypotonia were observed in at least 15% of individuals in a cohort of 136 16p11.2 deletion carriers. [5] Sensorineural or conductive hearing loss and paroxysmal kinesigenic choreoathetosis are observed in some individuals.
Chromosome 16 abnormalities; Chromosome 18 abnormalities; Chromosome 20 abnormalities; Chromosome 22 abnormalities; Cleft lip/palate; Cleidocranial dysostosis; Club foot; Congenital adrenal hyperplasia (CAH) Congenital central hypoventilation syndrome; Congenital diaphragmatic hernia (CDH) Congenital Disorder of Glycosylation (CDG) Congenital ...
Smith–Magenis syndrome (SMS), also known as 17p-microdeletion syndrome, is a microdeletion syndrome characterized by an abnormality in the short (p) arm of chromosome 17. [1] It has features including intellectual disability , facial abnormalities, difficulty sleeping, and numerous behavioral problems such as self-harm.