Hemoglobin H Disease; Hbh

Description

Hemoglobin H disease is a subtype of alpha-thalassemia (see {604131}) in which patients have compound heterozygosity for alpha(+)-thalassemia, caused by deletion of one alpha-globin gene, and for alpha(0)-thalassemia, caused by deletion in cis of 2 alpha-globin genes (summary by Lal et al., 2011). When 3 alpha-globin genes become inactive because of deletions with or without concomitant nondeletional mutations, the affected individual has only 1 functional alpha-globin gene. These people usually have moderate anemia and marked microcytosis and hypochromia. In affected adults, there is an excess of beta-globin chains within erythrocytes that will form beta-4 tetramers, also known as hemoglobin H (summary by Chui et al., 2003).Hb H disease is usually caused by the combination of alpha(0)-thalassemia with deletional alpha(+)-thalassemia, a combination referred to as 'deletional' Hb H disease. In a smaller proportion of patients, Hb H disease is caused by an alpha(0)-thalassemia plus an alpha(+)-thalassemia point mutation or small insertion/deletion. Such a situation is labeled 'nondeletional' Hb H disease. Patients with nondeletional Hb H disease are usually more anemic, more symptomatic, more prone to have significant hepatosplenomegaly, and more likely to require transfusions (summary by Lal et al., 2011).While most thalassemia-related hydrops fetalis is caused by the lack of all alpha-globin genes, there are reports of fetuses with Hb H disease that developed the hydrops fetalis syndrome; see {236750}.

Clinical Features

Top most frequent phenotypes and symptoms related to Hemoglobin H Disease; Hbh

  • Cognitive impairment
  • Anemia
  • Hepatomegaly
  • Edema
  • Splenomegaly
  • Pneumonia
  • Hepatosplenomegaly
  • Jaundice
  • Hemolytic anemia
  • Hydrops fetalis

And another 9 symptoms. If you need more information about this disease we can help you.

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Incidence and onset information

— Currently we don't have prevalence information about this disease (Not enough data available about incidence and published cases.)
No data available about the known clinical features onset.

Alternative names

Hemoglobin H Disease; Hbh Is also known as alpha-thalassemia, hemoglobin h type, hemoglobin h disease, deletional.

Researches and researchers

Currently, we don't have any information about doctors, researches or researchers related to this disease. Please contact us if you would like to appear here.


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Hemoglobin H Disease; Hbh Recommended genes panels

Panel Name, Specifity and genes Tested/covered
GeneAware Complete Panel Version 2 (Female).

By Baylor Miraca Genetics Laboratories (United States).

RMRP, BCS1L, SACS, BLM, SGCA, SGCB, SGCG, SGSH, SLC12A6, SLC17A5, SLC22A5, SLC25A13, SLC25A15, SLC26A2, SLC35A3, SLC7A7, SMN1, SMPD1, BTD, BTK , (...)

View the complete list with 139 more genes
Specificity
2 %
Genes
100 %
GeneAware Complete Panel Version 2 (Male).

By Baylor Miraca Genetics Laboratories (United States).

RMRP, BCS1L, SACS, BLM, SGCA, SGCB, SGCG, SGSH, SLC12A6, SLC17A5, SLC22A5, SLC25A13, SLC25A15, SLC26A2, SLC35A3, SLC7A7, SMN1, SMPD1, BTD, TGM1 , (...)

View the complete list with 129 more genes
Specificity
2 %
Genes
100 %
GeneAware Basic Panel Version 2 (Female).

By Baylor Miraca Genetics Laboratories (United States).

SMN1, CFTR, DMD, FMR1, HBA1, HBA2, HBB
Specificity
29 %
Genes
100 %
GeneAware Basic Panel Version 2 (Male).

By Baylor Miraca Genetics Laboratories (United States).

SMN1, CFTR, HBA1, HBA2, HBB
Specificity
40 %
Genes
100 %
GeneAware ACMG/ACOG Panel Version 2 (Male).

By Baylor Miraca Genetics Laboratories (United States).

BLM, SMN1, SMPD1, MCOLN1, CFTR, FANCC, GBA, HBA1, HBA2, HBB, HEXA, ELP1, ASPA
Specificity
16 %
Genes
100 %
GeneAware ACMG/ACOG Panel Version 2 (Female).

By Baylor Miraca Genetics Laboratories (United States).

BLM, SMN1, SMPD1, MCOLN1, CFTR, DMD, FANCC, FMR1, GBA, HBA1, HBA2, HBB, HEXA, ELP1, ASPA
Specificity
14 %
Genes
100 %
Alpha Globin Gene Sequencing.

By UCSF Molecular Diagnostics Laboratory University of California, San Francisco (United States).

HBA1, HBA2
Specificity
100 %
Genes
100 %
Alpha Thalassemia.

By UCSF Molecular Diagnostics Laboratory University of California, San Francisco (United States).

HBA1, HBA2
Specificity
100 %
Genes
100 %

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Sources and references

You can check the following sources for additional information.

OMIM ORPHANET Rare Disease Symptoms Checker

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