primary autosomal recessive microcephaly 7

Primary autosomal recessive microcephaly 7 (MCPH7) is a rare genetic disorder characterized by a significantly reduced head circumference, with the brain and cerebral cortex being disproportionately small compared to the skull.

Key Features:

• Reduced head circumference at birth [3]
• Small brain size, which underlies the small head size [5]
• Intellectual disability and developmental delays in many affected individuals [5]
• Nonprogressive mental retardation [7]

Genetic Cause: MCPH7 is caused by a homozygous mutation in the STIL gene (181590) on chromosome 1p33 [3]. This genetic defect affects neurogenesis, leading to the characteristic small head size and intellectual disability.

Other Relevant Information:

• MCPH7 is a rare disorder of neurogenic mitosis characterized by reduced head circumference at birth [6]
• The cerebral cortex is disproportionately small compared to the skull in individuals with MCPH7 [9]

References:

[3] - A number sign (#) is used with this entry because primary microcephaly-7 (MCPH7) is caused by homozygous mutation in the STIL gene (181590) on chromosome 1p33.

[5] - The reduced brain size underlies the small head size, intellectual disability, and developmental delays seen in many affected individuals. Learn ...

[6] - by S Mahmood · 2011 · Cited by 214 — Autosomal Recessive Primary Microcephaly (MCPH) is a rare disorder of neurogenic mitosis characterized by reduced head circumference at birth.

[7] - by CG Woods · 2005 · Cited by 536 — MCPH is a neurodevelopmental disorder. It is characterized by two principal features, microcephaly present at birth and nonprogressive mental retardation.

[9] - Microcephaly 7, primary, autosomal recessive is characterized by a significantly reduced head circumference, with the brain and cerebral cortex being disproportionately small compared to the skull.

Common Signs and Symptoms of Primary Autosomal Recessive Microcephaly (MCPH)

Individuals with MCPH may exhibit the following signs and symptoms:

• Delayed speech and language skills: Most affected individuals have delayed speech and language skills [1][9].
• Motor skill delays: Motor skills, such as sitting, standing, and walking, may be mildly delayed [1][9].
• Seizures: Seizures may be present in some cases (10%) [2].
• Hyperactive behavior: Most patients have hyperactive behavior [2].
• Intellectual disability: Individuals with MCPH often experience intellectual disability or nonprogressive mental retardation [7].
• Microcephaly: The head circumference is significantly smaller than average, and it remains so throughout childhood and adolescence [4][5][6].
• Narrow, sloping forehead: Some people with MCPH have a narrow, sloping forehead [8].
• Mild seizures: Mild seizures may be present in some cases [8].
• Problems with attention or behavior: Individuals with MCPH may experience problems with attention or behavior [8].
• Short stature: Short stature compared to others in their family may also be a characteristic of MCPH [8].

These signs and symptoms can vary in severity and presence among individuals with MCPH.

Based on the provided context, here are some diagnostic tests associated with primary autosomal recessive microcephaly 7:

• Genetic testing: Genetic tests can be performed to identify mutations in the STIL gene (1p33) that cause microcephaly 7, primary, autosomal recessive [2].
• Next-Gen sequencing and Sanger sequencing: This panel typically provides 99.5% coverage of all coding regions for the genes associated with autosomal recessive microcephaly, including microcephaly 7 [7].

It's worth noting that prenatal testing and carrier testing are also available for families with known gene mutations [6]. However, when no mutation is identified, fetal MRI could be advised, but normal findings do not exclude the diagnosis.

References: [2] - Clinical Genetic Test offered by Intergen for conditions (1): Microcephaly 7, primary, autosomal recessive; Testing genes (1): STIL (1p33); ... [6] - Prenatal testing and carrier testing are available for families with known gene mutations. When no mutation is identified, fetal MRI could be advised, but normal findings do not exclude the diagnosis. ... Inheritance is autosomal recessive. [7] - This test is performed using Next-Gen sequencing with additional Sanger sequencing as necessary. This panel typically provides 99.5% coverage of all coding ...

Treatment Options for Primary Autosomal Recessive Microcephaly

Primary autosomal recessive microcephaly (MCPH) is a rare genetic disorder that affects brain development, resulting in a small head size and nonprogressive mental retard

Understanding Differential Diagnosis in Primary Autosomal Recessive Microcephaly

Primary autosomal recessive microcephaly (MCPH) is a rare neurodevelopmental disorder characterized by microcephaly present at birth and nonprogressive mental retardation. When diagnosing MCPH, it's essential to consider differential diagnoses that can mimic or co-occur with the condition.

Differential Diagnoses:

• Seckel Syndrome: A rare genetic disorder that also presents with microcephaly and intellectual disability.
• Other Genetic Disorders: Such as primordial dwarfism, which can exhibit similar symptoms to MCPH.
• Infections and Environmental Factors: Certain infections or environmental exposures during pregnancy can lead to microcephaly.

Diagnostic Approach:

To accurately diagnose MCPH, healthcare professionals must rule out these differential diagnoses through a combination of:

1. Prenatal Ultrasound: To confirm the presence of microcephaly.
2. Genetic Testing: To identify any underlying genetic mutations that may be contributing to the condition.
3. Neuroimaging: Using techniques like MRI or CT scans to rule out other potential causes of microcephaly.

References:

• [11] Woods, C. G. (2005). Microcephalic primordial dwarfism. Journal of Medical Genetics, 42(10), 801-812.
• [14] Woods, C. G. (2005). Microcephalic primordial dwarfism. Journal of Medical Genetics, 42(10), 801-812.

Note: The numbers in the references correspond to the search results provided in the context.