Allan-Herndon-Dudley Syndrome: Should the Locus for This Hereditary Spastic Paraplegia Be Designated SPG 22?

White matter abnormalities and dystonic motor disorder associated with mutations in the SLC16A2 gene

“…Other reported MRI abnormalities in single cases of AHDS have been non‐specific, including subtle cortical and subcortical atrophy, 17 mild cerebellar atrophy, 19 and high T2 signal in the putamina 12,18 . Taking into account an evolving spastic paraparesis in a male with profoundly reduced myelin on MRI, one of our participants (participant 1) had an initial diagnosis of Pelizaeus–Merzbacher disease, a disorder of myelination caused by mutations in the PLP1 gene on Xq22 encoding proteolipid protein 1, thus indicating that SLC16A2 gene mutation screening should be considered in the differential diagnosis of males presenting with features of Pelizaeus–Merzbacher‐like disease or X‐linked spastic paraplegia (SPG2), 20 a condition allelic to Pelizaeus–Merzbacher disease. Similarly, participants 4 and 5 were also thought to have a disorder of brain myelination on the basis of their neuroimaging findings.…”

White matter abnormalities and dystonic motor disorder associated with mutations in the SLC16A2 gene

“…Other reported MRI abnormalities in single cases of AHDS have been non‐specific, including subtle cortical and subcortical atrophy, 17 mild cerebellar atrophy, 19 and high T2 signal in the putamina 12,18 . Taking into account an evolving spastic paraparesis in a male with profoundly reduced myelin on MRI, one of our participants (participant 1) had an initial diagnosis of Pelizaeus–Merzbacher disease, a disorder of myelination caused by mutations in the PLP1 gene on Xq22 encoding proteolipid protein 1, thus indicating that SLC16A2 gene mutation screening should be considered in the differential diagnosis of males presenting with features of Pelizaeus–Merzbacher‐like disease or X‐linked spastic paraplegia (SPG2), 20 a condition allelic to Pelizaeus–Merzbacher disease. Similarly, participants 4 and 5 were also thought to have a disorder of brain myelination on the basis of their neuroimaging findings.…”

Swimming in Deep Water: Zebrafish Modeling of Complicated Forms of Hereditary Spastic Paraplegia and Spastic Ataxia

“…Allan-Herndon-Dudley syndrome (AHDS), a rare disorder of brain development with neuromuscular involvement, is characterized by a combination of severe intellectual disability, spastic paraplegia, and disturbed thyroid hormone (TH) parameters (Bohan and Azizi, 2004). The AHDS locus was identified on chromosome X, and this condition occurs exclusively in young males.…”

“…The AHDS locus was identified on chromosome X, and this condition occurs exclusively in young males. Bohan and Azizi (2004) suggested that AHDS was the fourth locus for X-linked spastic paraplegia, and proposed the term "SPG22" for the locus Xq21 that encompasses the AHDS region (Bohan and Azizi, 2004). AHDS is caused by mutations in MCT8, a gene that encodes a TH transporter.…”

Genetic disorders of thyroid metabolism and brain development

“…Of note, absent or reduced myelination in the context of an evolving spastic paraplegia in males with AHDS may lead to the misdiagnosis of Pelizaeus‐Merzbacher disease, a disorder of myelination due to mutations in the PLP1 gene on Xq22. SLC16A2 mutation screening has therefore to be considered in males presenting with features of Pelizaeus‐Merzbacher disease or X‐linked spastic paraplegia, an allelic condition, once PLP1 mutations have been excluded.…”

White matter abnormalities and dystonic motor disorder associated with mutations in the SLC16A2 gene

“…Other reported MRI abnormalities in single cases of AHDS have been non‐specific, including subtle cortical and subcortical atrophy, 17 mild cerebellar atrophy, 19 and high T2 signal in the putamina 12,18 . Taking into account an evolving spastic paraparesis in a male with profoundly reduced myelin on MRI, one of our participants (participant 1) had an initial diagnosis of Pelizaeus–Merzbacher disease, a disorder of myelination caused by mutations in the PLP1 gene on Xq22 encoding proteolipid protein 1, thus indicating that SLC16A2 gene mutation screening should be considered in the differential diagnosis of males presenting with features of Pelizaeus–Merzbacher‐like disease or X‐linked spastic paraplegia (SPG2), 20 a condition allelic to Pelizaeus–Merzbacher disease. Similarly, participants 4 and 5 were also thought to have a disorder of brain myelination on the basis of their neuroimaging findings.…”

Swimming in Deep Water: Zebrafish Modeling of Complicated Forms of Hereditary Spastic Paraplegia and Spastic Ataxia

“…Allan-Herndon-Dudley syndrome (AHDS), a rare disorder of brain development with neuromuscular involvement, is characterized by a combination of severe intellectual disability, spastic paraplegia, and disturbed thyroid hormone (TH) parameters (Bohan and Azizi, 2004). The AHDS locus was identified on chromosome X, and this condition occurs exclusively in young males.…”

“…The AHDS locus was identified on chromosome X, and this condition occurs exclusively in young males. Bohan and Azizi (2004) suggested that AHDS was the fourth locus for X-linked spastic paraplegia, and proposed the term "SPG22" for the locus Xq21 that encompasses the AHDS region (Bohan and Azizi, 2004). AHDS is caused by mutations in MCT8, a gene that encodes a TH transporter.…”

Genetic disorders of thyroid metabolism and brain development

“…Of note, absent or reduced myelination in the context of an evolving spastic paraplegia in males with AHDS may lead to the misdiagnosis of Pelizaeus‐Merzbacher disease, a disorder of myelination due to mutations in the PLP1 gene on Xq22. SLC16A2 mutation screening has therefore to be considered in males presenting with features of Pelizaeus‐Merzbacher disease or X‐linked spastic paraplegia, an allelic condition, once PLP1 mutations have been excluded.…”

White matter abnormalities and dystonic motor disorder associated with mutations in the SLC16A2 gene

“…Other reported MRI abnormalities in single cases of AHDS have been non‐specific, including subtle cortical and subcortical atrophy, 17 mild cerebellar atrophy, 19 and high T2 signal in the putamina 12,18 . Taking into account an evolving spastic paraparesis in a male with profoundly reduced myelin on MRI, one of our participants (participant 1) had an initial diagnosis of Pelizaeus–Merzbacher disease, a disorder of myelination caused by mutations in the PLP1 gene on Xq22 encoding proteolipid protein 1, thus indicating that SLC16A2 gene mutation screening should be considered in the differential diagnosis of males presenting with features of Pelizaeus–Merzbacher‐like disease or X‐linked spastic paraplegia (SPG2), 20 a condition allelic to Pelizaeus–Merzbacher disease. Similarly, participants 4 and 5 were also thought to have a disorder of brain myelination on the basis of their neuroimaging findings.…”

Swimming in Deep Water: Zebrafish Modeling of Complicated Forms of Hereditary Spastic Paraplegia and Spastic Ataxia

“…Allan-Herndon-Dudley syndrome (AHDS), a rare disorder of brain development with neuromuscular involvement, is characterized by a combination of severe intellectual disability, spastic paraplegia, and disturbed thyroid hormone (TH) parameters (Bohan and Azizi, 2004). The AHDS locus was identified on chromosome X, and this condition occurs exclusively in young males.…”

“…The AHDS locus was identified on chromosome X, and this condition occurs exclusively in young males. Bohan and Azizi (2004) suggested that AHDS was the fourth locus for X-linked spastic paraplegia, and proposed the term "SPG22" for the locus Xq21 that encompasses the AHDS region (Bohan and Azizi, 2004). AHDS is caused by mutations in MCT8, a gene that encodes a TH transporter.…”

Genetic disorders of thyroid metabolism and brain development

“…Of note, absent or reduced myelination in the context of an evolving spastic paraplegia in males with AHDS may lead to the misdiagnosis of Pelizaeus‐Merzbacher disease, a disorder of myelination due to mutations in the PLP1 gene on Xq22. SLC16A2 mutation screening has therefore to be considered in males presenting with features of Pelizaeus‐Merzbacher disease or X‐linked spastic paraplegia, an allelic condition, once PLP1 mutations have been excluded.…”