Double Heterozygosity

Description: Having 2 genes for dominant conditions. Pertinent for two people, each having a dominant skeletal dysplasia, as their children will have the possibility of inheriting two genes for skeletal dysplasias usually resulting in a severe or lethal skeletal dysplasia.

Achondroplasia-hypochondroplasia complex in a newborn infant.
Source/Author: Huggins MJ, Smith JR, Chun K, Ray PN, Shah JK, Whelan DT.; Am J Med Genet. 1999 Jun 11;84(5):396-400. 
Abstract
Case report of a patient with achondroplasia and hypochondroplasia - prenatally and postnatally.

Achondroplasia-hypochondroplasia complex.
Source/Author: Sommer A, Young-Wee T, Frye T.; Am J Med Genet. 1987 Apr;26(4):949-57. 
Abstract
Case report of a teenager with both achondroplasia and hypochondroplasia.

Compound heterozygosity for the Achondroplasia-hypochondroplasia FGFR3 mutations: prenatal diagnosis and postnatal outcome.
Source/Author: Chitayat D, Fernandez B, Gardner A, Moore L, Glance P, Dunn M, Chun K, Sgro M, Ray P, Allingham-Hawkins D.; Am J Med Genet. 1999 Jun 11;84(5):401-5. 
Abstract
Report on a newborn with achondroplasia and hypochondroplasia including clinical information and prenatal diagnosis details.

Compound heterozygosity for the Achondroplasia-hypochondroplasia FGFR3 mutations: prenatal diagnosis and postnatal outcome.
Source/Author: Chitayat D, Fernandez B, Gardner A, Moore L, Glance P, Dunn M, Chun K, Sgro M, Ray P, Allingham-Hawkins D.; Am J Med Genet. 1999 Jun 11;84(5):401-5. 
Abstract
Case report of prenatal diagnosis of parents, one with achondroplasia and one with hypochondroplasia, and their child who inherit genetic mutations for both conditions.

Double Dominance
Source/Author: Mary Ellen Little, ADN RNC 
Support group
Web site designed by the LPA bereavement coordinator for LPA. Support services for couples having a baby affected with double dominant or double heterozygote dwarfism (2 genetic doses of dwarfism) causing a lethal condition.

Double heterozygosity for pseudoachondroplasia and spondyloepiphyseal dysplasia congenita
Source/Author: Unger S, Korkko J, Krakow D, Lachman RS, Rimoin DL, Cohn DH.; Am J Med Genet. 2001 Nov 22;104(2):140-6. 
Abstract
Case report of a child with both pseudoachondroplasia and spondyloepiphyseal dysplasia. Discussion of molecular genetics and clinical outcome of child.

Double heterozygosity in bone growth disorders: four new observations and review.
Source/Author: Flynn MA, Pauli RM.
Abstract
Reviews the following cases of double heterozygosity: achondroplasia & spondyloepiphyseal dysplasia congenita, achondroplasia & pseudoachondroplasia, achondroplasia & osteogenesis imperfecta type I, achondroplasia & hypochondroplasia, pseudoachondroplasia & spondyloepiphyseal dysplasia congenita, Leri-Weill Dyschondrosteosis & hypochondroplasia/achondroplasia, osteogenesis imperfecta & pseudoachondroplasia.

Lethal skeletal dysplasia owing to double heterozygosity for achondroplasia and spondyloepiphyseal dysplasia congenita.
Source/Author: Young ID, Ruggins NR, Somers JM, Zuccollo JM, Rutter N.; J Med Genet. 1992 Nov;29(11):831-3 
Abstract
Case report of newborn thought to have inherited pseudoachondroplasia from one parent and SEDc from the other parent.

Lung hypoplasia and severe pulmonary hypertension in an infant with double heterozygosity for spondyloepiphyseal dysplasia congenita and achondroplasia.
Source/Author: Gunthard J, Fliegel C, Ohnacker H, Rutishauser M, Buhler E.; Clin Genet. 1995 Jul;48(1):35-40. 
Abstract
Case report of newborn with achondroplasia and SEDc.

Patient with double heterozygosity for achondroplasia and pseudoachondroplasia, with comments on these conditions and the relationship between pseudoachondroplasia and multiple epiphyseal dysplasia, Fairbank type.
Source/Author: Langer LO Jr, Schaefer GB, Wadsworth DT. 
Abstract
Case report of a patient with achondroplasia and pseudoachondroplasia. Also discussed the relationship between pseudoachondroplasia and MED, Fairbank type.