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R
i lo n di truy n
RETT’S SYNDROME
What is Rett’s syndrome?
This is a neurodevelopmental disorder of brain grey matter.
Causes
•
Mutation of the methyl-CpG binding protein-2 (MECP2) gene.
Signs and symptoms
•
Neurological dysfunction, e.g.:
○
Ataxia.
○
Hypotonia.
○
Inability to walk or altered gait.
○
Chorea.
•
Autistic behaviour, e.g.:
○
Lack of eye contact.
○
Lack of theory of mind.
○
Decreased social interaction.
○
Speech deficit.
○
Screaming.
Investigations
•
DNA sequencing of MECP2 gene is diagnostic.
Treatment
•
Conservative: parent education.
•
Medical: treatment of complications.
Bi n ch ng
•
Lo n nh p tim
•
Đ ng kinh
•
Trào ngư c d dày th c qu n
•
Loãng xương.
AICARDI SYNDROME
What is Aicardi syndrome?
This is an X-linked recessive condition in which there is partial or
a complete absence of the corpus callosum. Retinal abnormalities and
seizures are also present.
Causes
The exact cause remains unknown but it is thought to be due to new
mutations that are passed genetically to offspring via X-linked recessive
inheritance.
Signs and symptoms
•
Infantile spasms.
Investigations
•
Radiology: CT or MRI scan confirming corpus callosum agenesis.
Treatment
•
Conservative: parent education. Referral to speech and language
therapy, neuropsychologist, neurology and physiotherapy.
•
Medical: there is no specific treatment. Manage epilepsy, see pages 146–151.
Complications
•
Hydrocephalus.
•
Porencephalic cysts.
H I CH NG KLINEFELTER
H i ch ng Klinefelter là gì?
Là m t h i ch ng x y ra nam gi i khi có thêm m t NST
gi i tính X, tr thành XXY
Nguyên nhân
•
Thêm m t NST X
Tri u ch ng
•
Thi u năng sinh d c
•
Dài các chi
•
D y thì mu n
•
Vú to
•
Vô sinh
MAP 13.3 Di truy n gen l n liên k t NST X (ti p)
Xét nghi m
•
Ch n đoán trư c sinh.
•
N ng đ FSH và LH.
Đi u tr
•
Giáo d c b nh nhân và ngư i nhà. Tư v n di truy n
•
Thu c: Không có đi u tr đ c hi u. Đi u tr các b nh ph i h p như tr m
c m depression, là b nh thư ng g p trong nhóm này
Bi n ch ng
•
Vô sinh
•
Tr m c m
Map 13.3 Di truy n gen l n liên k t NST X
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